BIBLIOGRAPHY PALADA, DENSON B. APRIL 2009....
BIBLIOGRAPHY
PALADA, DENSON B. APRIL 2009. Occurrence of Carabid Beetles and
Earwigs in Strawberry Farms in La Trinidad, Benguet. Benguet State University, La
Trinidad, Benguet.
Adviser: Bonie S. Ligat, MSc
ABSTRACT
The study was conducted in three Strawberry farms in La Trinidad, Benguet from
August to October 2008. Improvised pitfall traps and quadrant metal were used to collect
insects once a week. The specimens were counted, identified and recorded. The study
aimed to to identify the species of Ground Beetles and Earwigs present in the farm, to
asses the population of Ground Beetles and Earwigs and to document the insects with the
use of Digital Camera.
Three (3) species of Carabid Beetles were collected: Chlaenius tricolor,
Bembidioni versicolor, and the Patrobus longicornis. There were also three species of
Earwigs: the Anisolabis maritima, Euborellia annulipes, and Forficula auricularia.
The population of carabid beetles in three months ranged from 12 to 46 while the
Earwigs ranged from 47 to 53.
TABLE OF CONTENTS
Pages
Bibliography………………………………………………………….…………. i
Abstract ………………………………………………………………….……… i
Tables of Contents………………………………………………………………. ii
INTRODUCTION……………………………………………………………… 1
REVIEW OF LITERATURE………………………………………….…….… 4
MATERIALS AND METHODS……………………………………………… 10
RESULTS AND DISCUSSION ……………………………………………… 18
Species of Carabid Beetles…………………….. ……………………… 18
Species of Earwigs……………………………………………………… 22
Other Insects…………………………………………………………… 26
SUMMARY, CONCLUSION AND RECOMMENDATION ……………… 27
Summary ……………………………………………………………… 27
Conclusion …………………………….……………………………… 27
Recommendation …………………………………………………….. 28
LITERATURE CITED………………………………………………………. 29
APPENDICES ………………………………………………………………. 31
ii
INTRODUCTION
The growing hazards that go along with the heavy use of chemicals to produce
man’s food and other basic commodities has enlightened the enthusiasm of many
institutions and workers to develop alternative measures to minimize the use of chemicals
in agricultural and industry. One of their objectives is to minimize the pollution of our
environment and its resultant effect on human health. The Philippine Council for
Agriculture, Forestry and Natural Resources Research and Development through its
Agricultural Resources Management Research Division, has already taken significant
strides.
President Gloria Macapagal Arroyo declared Executive Order 481, a state’s
policy to promote and develop Organic Agriculture in the country. on July 27, 2005
which is called the Organic Agriculture (OA) including all agricultural systems that
promote environmentally, socially, and economically sound production of food and
fibers. It sprang from the need to produce safe food as an alternative to alleviate over
exploitation and degradation of natural resources. Since then the policy was executed,
Benguet State University is now spearhead the Province of Benguet in promoting
Organic Agriculture especially in the Vegetable Industry.
In support to the institution’s program, research on different Organic practices
have been started and this including the use of biological control against pest such as
insect predators, parasitoids, and pathogens.
Beneficial insects like Carabid beetles and Earwigs/ predatory that feed on
immature pests. Carabidae is a large family with more than 40,000 species worldwide.
Most species are carnivorous, and some run swiftly to catch their prey. Although there is
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
2
a variation on their body shape and coloring, most are shiny, black, and have rigid elytra.
Gourd beetles in the genus Brachinus are commonly known as bombardier beetles;
ground beetles in the family Cicindelidae are known as tiger beetles. Unlike most
species of Carabidae, which are nocturnal, tiger beetles are active diurnal hunters, and
often brightly colored. All species except the primitive Paussinae, have a groove on their
front tibia bearing a comb hairs, for cleaning their antennae, common habitats are under
the bark of trees, under logs, or amongst rocks or sand by the edge of ponds and rivers
(Drees et al., 1999).
The earwig is one of the important insect because most earwigs feed on decaying
plant matter and some species are predatory and feed on a variety of other insects. They
can be easily identified by their forceps-like pincers (cerci), which they use for defense.
Many species are wingless and live in the soil or in enclosed spaces. Predatory earwig
will enter plant stems of stem boring and they are ussually hide during daytime and
become active at night.
Once Organic Farming becomes fully implemented in the country, Carabid
beetles, earwigs and other important insects will be conserved and reared in mass for
biological control against insect pests. It will also observe if the ground beetles
(Carabidae and Earwigs) are present in strawberry farms. Furthermore, it will provide a
benchmark data for future researchers who wish to study more on the different ground
insects in strawberry farms.
The study was conducted to Asses the population of ground beetles and earwigs
on strawberry farms in La Trinidad, Benguet; identify species of ground beetles and
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
3
earwigs and record other ground insects caught in the trap and encountered in the
Quadrant Metal.
The research concentrated on the occurrence of ground beetles and earwigs on
strawberry farms. This is because these insects are important predators that could be used
as biological control. The study was conducted in three areas of La Trinidad: Longlong,
Swamp area, and at the Entomology field located at Balili. The study was conducted from
August to 0ctober 2008.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
REVIEW OF LITERATURE
Carabid Beetles
Some soil coleopterans are predators of other soil animals, others are
Phytophagous. Include in the latter group are the well known larvae of scarabs and
chaffers which feed upon plant roots (Richards, 1974).
Biology
Larvae of some species are considered to mainly carnivorous and wide-
ranging, feeding on some soft-bodied insects. Euborellia annulipes (Lucas), the ring-
legged earwig has been recorded from beneath stones, debris or litter of various
kinds in compost heaps or dung in which it may be numerous, or in fruits, among
vegetation, or in houses (Stehr, 1987).
The ground beetles are predaceous, the prey consisting mainly of insects but
including also earthworms, snails, etc., though a few species are questionably
phytophagous and others at times partake of plant food in addition to insect diet. The
insect feeders attack lepidopterous larvae and naked pupae more generally than they
do the immature stages of other orders, though a number of species are recorded are
feeding extensively upon scarabeid grubs in the soil. The adults are predominantly
ground dwellers, and they carry their activities mainly at night. They may can be
found also in various protected locations, such as under stones and debris and the
loose bark of trees, or they may inhabit distinct burrows (Stehr, 1987).
The feeding habits of the adult beetles vary considerably from those of the
larvae. Thus, a number of species of Carabus, Craspedonotus, and other genera have
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
5
been recorded as attacking and feeding upon adult beetles, snails, etc. Calosoma
inquisitor L. of Europe is particularly abundant in areas bearing broad-leaved trees,
upon the foliage of which it searches for caterpillars. The variety of food consumed
by the adults is appreciably greater than that consumed by the larvae, partly owing to
their greater agility, enabling them to capture insects that can escape from the larvae.
Feeding may be very rapid, consisting of the biting or tearing away of portions of the
tissue of the victim after the integument has been broken, or it may solely by the
ingestion of liquid materials, resulting from the preoral digestion of the host tissues,
in addition to the body fluid (Clausen, 1962).
Carabid ground beetles go through egg, larval, and pupal stages of
development before reaching adulthood. Development from the egg to the adult stage
generally takes about a year. The adults of some species lay their eggs in specially
constructed mud or twig cells, while others lay their eggs in debris. Some adults may
live 2 to 3 years (Carey, 2005).
The Sidewalk Carabid a ground beetle has almost 2200 species in the United
States and throughout the world. The Sidewalk Carabid was chosen to represent the
family simply because it is the most commonly encountered species in residential
areas. These are good bugs. They feed on any kind of ground-inhabiting larvae and
insect eggs. They live in ground covers and in compost piles. In the garden they
prefer to eat cut worms, so gardeners love to see these beetles take up
residence. Ground beetles range in size from about 2 mm to 25 mm (1/8 inch to 1
inch). Most tend to be black, but there are a wide variety of colors represented in the
various species. Some are dark brown and sometimes have a bronze or green metallic
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
6
sheen. Sidewalk Carabid is shiny black and about 15 mm long. These are robust
beetles with proportionately large powerful jaws.Ground beetles are found
everywhere in the United States, Canada, and throughout the world. The Sidewalk
Carabid is largely restricted to the larger towns and cities, but has been gradually
working its way into the countryside. It is an introduced species, originally coming
from Europe (Maddison, 2006).
Ecology
Most carabids are omnivorous (feeding on both plants and animals) and
polyphagous (being able to use a wide range of foods), feeding on live prey, carrion
and plant material. Some species however are specialist feeders, i.e. Harpalus rufipes
(the Strawberry Seed Beetle) on seeds, Loricera pilicornis (the Springtail Beetle) on
Collembola and Abax parallelopipedus and Cychrus caraboides on slugs and snails.
Offonus species feed exclusively on the seeds of Umbellifers, this is known as
spermophagy. The larvae are always carnivorous if the adults are. Many Carabids
find their food by random foraging, but specialist feeders tend to use chemical cues.
Pterostichus cupreus has a two dimensional search pattern until it finds an aphid at
the base of a plant. Finding the aphid stimulates it to a three dimensional search
pattern, i.e. it climbs the plant looking for more aphids. Most species of Ground
beetles are cannibalistic given the opportunity. Abax parallelopipedus is unusual in
that it is not cannibalistic it can often be found under rotten logs in woodlands
(Anonymous, 2006).
Predacious ground beetles also referred to as carabids, belong to a large
family of beneficial beetles called the Carabidae. There are several thousand species
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
7
of these beetles in North America alone. The adult beetles range from 1/8-inch to 1¼
inches long. Variable in shape, they are usually elongate, heavy bodied, and slightly
or distinctly tapered at the head end while generally dark in color (dark brown to
black), some beetles are an attractive purple or metallic green, or are multi-colored, as
some case of some tropical species. Ground beetles are fast-moving insects, which
generally have prominent, long legs and fairly threadlike antennae. Most native
species to the area are found in the wetter regions (or around waterways). Larval
ground beetles are elongate and wormlike in appearance; most live in burrows in the
soil or in leaf litter or other debris. Both larval and adult ground beetles have
powerful and prominent mandibles. This is an adaptation for their predacious life
style. Most ground beetles in this area feed on a varied diet of insects and insect-like
creatures, many of which are garden or house pests, such as cutworms or house fly
maggots. One specific group of ground beetles feeds on snails and slugs. Some
occasionally feed on earthworms, but their beneficial feeding habits, in general, far
outweigh any detrimental effects they may have on local earthworm populations. A
few species will even feed on pollen or seeds. When carabids are disturbed they often
demonstrate some form of defensive behavior. Many northwestern native species
secrete chemicals that have a bad odor. This behavior is thought to be a deterrent to
animals which might eat them (Carey, 2005).
Dermaptera-Earwigs
Acccording to Alford (1999), Earwigs are polyphagous and are beneficial and
will destroy large numbers of Aphids and other pests. They are nocturnal insects, and
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
8
usually hide during the daytime amongst curled leaves, under loose bark and in other
sheltered situations.
Earwigs are medium-sized insects that superficially resemble certain types of
beetles. They are elongate insects with a pair of pincer-like cerci at the tip of the
abdomen. These insects may or may not have wings. Those with wings have front
wings that form short, leathery coverings for the large membranous hind wings.
Earwigs have chewing mouthparts and three-segmented tarsi and show little change
in body form during growth (Gradual metamorphosis). Some species with gland and
openings on the gland that emit a foul-smelling liquid believe to serve as protection
from enemies (Pedigo and Rice, 1989).
Earwigs are active at night and hide during the day. They feed mostly on
decaying organic matter, but few occasionally feed on plants, and others are
predaceous.
Earwigs as Pest Control
Earwigs can be considered in some ways as beneficial insect and part of the
garden, especially when they prey on other insects, but they can become a nuisance
because of their habit of positioning themselves within leaves and feeding on soft
plant tissues. They prefer cool, moist places, and a rolled up damp newspaper placed
where earwig activity is suspected can be effective in collecting them. The newspaper
can then either be discarded or shaken out. Placing diatomaceous earth in key spots
around the home (bathroom, baseboards, window frames) can be a long-term
repellent (Rankin and Palmer, 2003).
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
9
Hundreds of thousands of these beneficial predators are now being produced
and released in corn farms infested with asian corn borer, cutworm, corn earworm,
armyworm, grasshoppers, and semi-looper (Fernandez, 2008).
Cotton Development Authority (CODA) also developed a technology on the
use of earwigs against the flower weevil on cotton. The earwigs both the nymph and
adult feed on the larva and pupa of flower weevils. Their life span ranges from 82-
104 days. These predators are mass-reared and are released in the field when flower
weevils are present. Initial population of the predator can be collected from the soil
and shed young bolls. It can be mass-produced in the laboratory using larva of
Tribolium sp. or its hosts. Three-week old earwig nymphs and adults at 9,000 to
11,000 per hectare can be released at 68, 82 and 89 days after planting (DAP) or on
the first occurrence of flower weevil. The first release should coincide with the
hatching of the first generation of flower weevil eggs. The predation efficiency of
earwigs ranges from 20.44 to 23.15 percent. Using earwigs, seedcotton yield is
expected to increase by 19.15 to 22.18 percent (Anonymous, 2008).
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
MATERIALS AND METHODS
Materials
The materials used were; improvised pitfall traps (75 pieces) made of plastic
bottles with measuring about 8 cm diameter with 11 cm tall with plastic shade, 1
kilogram detergent tide powder, forceps, microwavable plastic container, camera,
microscope, and one quadrant metal trap made up of tin can (27 X 27 X17 cm), and
improvised sieve.
Methodology
Location. The study was conducted in th three strawberry farms in La Trinidad,
Benguet measuring 500 sq m each particularly at the Entomology field located at Balili
(Figure 1), Longlong (Figure 2), an Swamp area (Figure 3). The Strawberry plants in
Balili are at their senescence stage, at Longlong the strawberry were bearing fruits while
at Swamp the strawberry are on their vegetative stage.
Pit
trap. An improvised pitfall trap was prepared using empty C2 plastic bottle
and used as shown in figure 4ab. The plastic trap was half-filled with water mixed with
tide detergent. The detergent was used as a repellant. Twenty five traps at each farm site
were arranged in transect (Figure 5). Each trap was put in a dug as shown in Figure 6. it
filled with water and the tip was elevated at least ½ inch above the ground. The traps
were provided with plastic shade against rain (Figure 4a) with 1 ½ distance from the
ground. The introduced pitfall traps were carefully observed one after it was introduced
and every week thereafter for 12 weeks. The water-detergent container was replenished
when necessary to keep the trapped insects in place prior to collection period. In
collecting the insects, the traps were decanted and sieved (Figure 8c).
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
11
Figure 1. The site at Balili with dry cogon grass as mulch
Figure 2. The site at Swamp with Polyethylene mulch
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
12
Figure 3.The site at Longlong with polyethylene as mulch
a
b
Figure 4. Improvised Pitfall trap cover. a.) Top view and b.) Side view
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
13
Figure 5. TheTransect Method
Figure 6. Top view of a Pitfall trap set up beside a Strawberry plant
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
14
Quadrant metal trap. Insects tend to hide during the day and they may forage in
the weeds outside the area. The quadrant metal was used to determine insects also outside
the experimental area. Hence, a quadrant metal trap (Figure 7) was improvised and used.
The quadrant metal trap was set up by pressing the side surface in areas outside the
strawberry fields where there are grasses. The area inside the trap was cleaned by
uprooting all the grasses. Samples of isects present inside the trap were gathered and
recorded. Afterwhich the grasses were removed and exposed the earwigs and Carabid
beetles that are ussually soil-bone.
The insects were gathered using forceps (Figure 8) and through an improvised
sieve. Insects were documented using Digital Camera with a white Background through a
microscope (Figure 9 & 10). Identification book and microscope were used to identify the
insects at the Mite Predators Rearing House ( Figure 11).
a
b
Figure 7. Quadrant metal trap. a.) Side view b.) top view
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
15
a
b
c
Figure 8. Materials used in the collection of specimens. a.) microwavable plastic,
b.) forceps, and c.) improvised sieve.
a
b
Figure 9. Materials used in identifying the specimens. a Microscope, and
b) identification book
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
16
Figure 10.The researcher identifying the collected insects.
Figure 11. The mite predator rearing house
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
17
The data gathered were:
1. Number of adult carabid beetles and earwigs.This is to determine the species and the
population of these insects in the three samplimg sites.
3. Photographs of insects collected. These were that were caught in the trap.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
RESULTS AND DISCUSSION
Carabid Beetles
Pit trap
Species. The monitored species of Carabid beetles that were collected are
presented in Table 1. There are three species as follows: Chlaenius tricolor (Figure 12),
Bembidioni versicolor (Figure 13), and Patrobus longicornis (Figure 14).
Population. There were eight adults of Chlaenius tricolor, four were collected
from Balili and also four from Swamp while it was absent in Longlong. Only one
Bembidioni versicolor was collected from Balili while it was absent from the two sites. In
terms Patrobus longicornis, one was collected from Balili, two from Longlong, and was absent
at the Swamp area.
Bembidioni versicolor was the least in number while Chlaenius tricolor has the
highest in number. The differenmce could be due to the observation that Bembidioni
versicolor stay at the side of the strawberry plots where the polyethylene mulch ends.
Thus, these were not caught at the pitfall traps that were situated at the strawberry plots.
Chlaenius tricolor on the other hand, was absent in Longlong. According to
Murray (2007), their habitat is usually moist areas, some and some are semiaquatic and
the site at Longlong was a little bit dry and elevated.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
19
Chlaenius tricolor. It measures 8-23 mm
in Size. Medium sized to large ground beetles.
They are Attractive, often with vivid metallic
coloration of head. Pronotum has distinctive
indentations. Head, pronotum, and elytra have
fine hairs (“setose”setae). front tarsomeres
1-3 of male are dilated, have spongy underside
Figure 14. Chlaenius tricolor (Murray) presumably used in mating. The covered
.
with hairs that lie flat.
Bembidioni versicolor. This has some
distinguishing characteristics that include elytra;
pronotum with relatively dull luster and
lateral margins parallel toward base.
Figure 15. Bembidioni versicolor (Murray)
Patrobus longicornis. It is the almost
the same with Bembidioni, the difference is the
long antennae and the color pure black color of
its body.
Figure 16. Patrobus longicornis (Eaton)
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
20
Table 1. Total population of carabid beetles species collected from the pitfall trap from
August to October 2009
===============================================================
SPECIES POPULATION
__________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
4
0
4
8
Bembidioni versicolor
1
0
0
1
Patrobus longicornis
1
2
0
3
TOTAL
6
2
4
12
===============================================================
Quadrant Metal Trap
Species. In this trap the species collected were similar to those trapped from the
pitfall.
There were Forty six (46) individuals of Carabid beetles from the three (3)
species. The highest in number was the Bembidioni versicolor which was gathered from
Longlong and Swamp while this was absent at Balili. Patrobus longicornis has seventeen
and it was gathered from the three sites. Chlaenius tricolor was not present neither from
the three sites.
There was no collected Chlaenius tricolor from the three sites. They may be
present in the side areas of the sites but the Quadrant Metal Method was done only once
in a month having the tendency that they were not encountered. Bembidioni versicolor is
absent in Balili this could be because the side areas was being disturbed by the
neighboring Garden prior to the removal of the grasses. On the other hand, they were
abundant in Swamp because the sides of the area were filled with different waste that
attracted other insects including larvae. These insects served as food for the Bembidioni
versicolor. Patrobus longicornis was encountered in the three sites
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
21
Table 2. Total population of carabid beetles encountered from the quadrant metal from
August to October 2009
===============================================================
SPECIES POPULATION
___________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
0
0
0
0
Bembidioni versicolor
0
6
23 29
Patrobus longicornis
2
2
13 17
TOTAL
2
8
36 46
===============================================================
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
22
Earwigs
Pitfall trap
Species. The collected species of Earwigs were the following: Anisolabis
maritima (Figure 15) Euborellia annulipes (Figure 16), and Forficula auricularia (Figure
17).
Population. In Balili, there were thirteen earwigs collected from the pitfall trap.
There were four Euborellia annulipes, nine Forficula auricularia and no Anisolabis
maritima were collected. There were also nineteen Earwigs collected in longlong, three
were Anisolabis maritima species, three Euborellia annulipes, and thirteen Forficula
auricularia. The three species were also present in Longlong, three Anisolabis maritima,
six Euborellia annulipes and six Forficula auricularia were collected. To sum it up there
were forty seven Earwigs collected from the whole duration of the implementation as of
August to October, 2008.
There were no caught Anisolabis maritima in the improvised pitfall trap from the
whole duration of the study in Balili. The reason could be the senescence stage of the
strawberry plant that affected the absence of the species. There were at least thirteen
collected Euborellia annulipes species from the three sites. Forficularia auricularia on
the other hand is also present in the three sites. They were abundant in Longlong maybe
because the place is suited them.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
23
Euborellia annulipes. Its size is
12-18 mm. They are medium-sized
dark-brown earwig with dark areas on
the light-yellow
legs ("black
armbands"). The species is wingless.
Adults have antennae with 14-16 the
third and fourth segments, (sometimes
Figure 15. Euborellia annulipes (Eaton) the fifth) from the end being white or
pale.
Forficula auricularia. Body
length ranges from 12 to 15 mm. Male
forceps 4 to 8 mm (Figs. 1-2); female
forceps 3 mm, tegmina 2 mm. Male
Figure 16. Forficularia auricularia (Murray) forceps vary from about half as long to
longer than the abdomen, broadened
basally, with crenulate teeth basally and
on beginning of curvature of inner
margin. Antennae hhave 14 or 15
segments. The adult is rich reddish-
brown, with wing covers and legs dull
yellow
brown, and the wings
completely developed.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
24
Anisolabis maritime. Wingless
form earwig with a medium-sized body.
Antenna with no white antenna
segment.
Figure 17. Annisolabis maritime (Eaton)
Table 3. Total population of earwig species collected from the pitfall trap from August
to October 2008
===============================================================
SPECIES POPULATION
___________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
0
3
3
6
Bembidioni versicolor
4
3
6
13
Patrobus longicornis
9
13
6
28
TOTAL 13
19
15
47
===============================================================
Quadrant Metal
Species. the species that were collected in this trap were similar to thew species
collected from the pitfall trap. They were the Anisolabis maritima, Euborellia annulipes
and Forficula auricularia
Population. Three Earwigs were collected from Balili, there is no Anisolabis
maritime, one Euborellia annulipes and two Forficula auricularia. fifteen individuals
were also collected from Longlong three Anisolabis maritime, four were Euborellia
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
25
annulipes and eight were Forficula auricularia.in. Swamp Area, there were thirty five
earwigs collected as follows: six Anisolabis maritima, six Euborellia annulipes and
twenty three Forficula auricularia. The Collected Earwigs has a total number of fifty
three of all the species collected, Forficula auricularia has the highest in number, having
a total number of thirty three, while there eleven and nine individuals for the Anisolabis
maritima and Euborellia annulipes respectively.
The same in the Pitfall trap, there were no encountered species of Anisolabis
maritima at Balili the reason could be they are absent in the area. Euborellia annulipes
and Forficula auricularia were also present in the three sites. In terms of the collected
individuals of the species, Balili got the lowest count. This could be affected by the
situation of the area wherein there were no grasses found at the side of the farm.
Table 4.Total population of earwigs species collected from the quadrant metal from
August to October 2008
===============================================================
SPECIES POPULATION
___________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
0
3
6
9
Bembidioni versicolor
1
4
6
11
Patrobus longicornis
2
8
23
33
TOTAL
3
15
35
53
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
26
Other Collected insects
Aside from the Earwigs and the Ground Beetles there were other collected insects
through the two methods from the three sites. These were the Ants, thrips, Cockroach,
Cricket, Dung Beetle, Housefly, Katydid, Lady Bug Beetle, Rove Beetle, and Snout
Beetle. Lady Bug Beetles and Rove beetles were known as insect predators/Beneficial
insects that were found. Lady Bug Beetles was collected from Balili while the Rove
Beetles were collected from from Longlong.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
SUMMARY, CONCLUSION AND RECOMMENDATION
Summary
The study was conducted at La Trinidad, Benguet from August to October, 2008
to assess the population of Ground Beetles and Earwigs, identify their species and record
other ground insects within the strawberry farms in La Trinidad, Benguet.
Three farms in La Trinidad, Benguet were established as collection sites.
Improvised pitfall trap and Quadrant Metal were used to collect insects. After collecting
species of insects, it was recorded and quantified. Gatherigns of Samples was done
weekly for the pitfall trap and once in a month for the Quadrant metal.
There were three species of carabid beetles collected from the three sites, the
Chlaenius tricolor, Bembidioni versicolor, and the Patrobus longicornis. There were also
three species of earwigs, the Anisolabis maritima, Euborellia annulipes, and Forficula
auricularia. Other insects also that were recorded were as follows: Ants, Thrips,
Cockroach, Cricket, Dung Beetle, Housefly, Katydid, Lady Bug Beetle, Rove Beetle, and
Snout Beetle. There were five insects belonging to the Order Coleoptera, two insects
belong to the Order Orthoptera, one insect also belong to Order Hymenoptera one and
one also from the order Blattodea.
Lady Bug Beetles and Rove beetles were known as insect predators/Beneficial
insects that were found. Lady Bug Beetles was collected from Balili while the Rove
Beetles were collected from Longlong.
Conclusion
There were Carabid Beetles and Earwigs in Strawberry farms in La Trinidad,
Benguet. There were three species of Carabid beetles (Claenius tricolor, Bembidioni
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
28
versicolor and, Patrobus longicornis). Earwigs were also present in the areas, there were
three species found from the three areas namely: Forficularia auricularia, Annisolabis
maritima and Euborellia annulipes.
The Ecological Society of America (ESA) concluded that the larval diets of
carabid beetles are carnivorous in general, and are divided into three types: insect larva
feeder (feed on lepidopteran and dipteran larvae), snail feeder and earthworm feeder.
Adult beetles of these three types tend to be omnivorous. While Hadley (2008) mentioned
that the earwig’s diet is highly variable. European earwigs feed at night on the foliage of
various flowers and garden plants. Most species prey on other insects and supplement
their diet with decaying organic matter found in soil or garbage. In addition to consuming
aphids, beetle larvae, and maggots.
With the presence of these important predators, the researcher concluded that the
three sites at Balili, Longlong and Swamp area are still good. We should conserve these
insects, as they are important that will help us control the insect pest in our farms.
Recommendation
It is recommended that further study more on Carabid Beetles and Earwigs should
be done for 1 year to know their activities, during summer, when there is typhoon or
heavy rain.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
LITERATURE CITED
ALFORD, D. V. 1999. A Textbook of Agricultural Entomology. 10 rue Casimir
Delavigne
75006, Paris, France. Blackwell Science Ltd. P. 59.
ANONYMOUS. 2008. Flowerweevil Control Without Chemical Pesticide. Retrieved
March 2, 2009 from http://coda.da.gov.ph/archives/flowerweevil_control.php
ANONYMOUS. 2006. Carabid Beetles. Retrieved July 8, 2008 from
http://www.earthlife.net/insects/carabids.html
CAREY, B. 2005. The Carabid Beetles. Retrieved July 10, 2008 from
http://gardening.wsu.edu/library/inse002/inse002.htm
CLAUSEN, C. P. 1962. Entomophagous Insects. USA, New York. Hafner Publishing
Company. Pp 528-529.
DREES, B. M. and J. JACKMAN. 1999. Field guide to Texas insects. Houston.
Retrieved May 20, 2008 from http://www.insects_beetles/Carabids/Article.html.
ECOLOGICAL SOCIETY OF AMERICA (ESA). 2005. Poster Session 30: Invertebrate
Ecology. Retrieved March 23, 2009 from
http://abstracts.co.allenpress.com/pweb/esa2005/document/49879.
FERNANDEZ, R. A. 2008. Earwig: Guardian of Ilocos corn farms . Retrieved February
28, 2009 from http://www.philstar.com/Article.aspx?articleid=411906
MADDISON, D. R. 2006. Carabid Beetles. Retrieved July 8, 2008 from
http://www.eduwebs.org/bugs/ground_beetles.htm
MURRAY, T. 2007. Carabid Information. Retrieved March 23, 2009 from
http://bugguide.net/node/view/14055
HADLEY, D. 2008. More about Earwigs. Retrieved March 23, 2009 from
http://insects.about.com/od/beetles/p/carabidae.htm
PEDIGO, L. P. and M. E. RICE. 1989. Entomology and Pest Management. Upper Saddle
River, New Jersey, Columbus, Ohio. Pearson Prentice Hall.
RANKIN, S. M. and J. O. PALMER. 2003. .http://en.wikipedia.org/wiki/Earwig#Pest
control
RICHARDS, B. N. 1974. Introduction to Soil Ecosystem. USA, New York. Longman
Group Limited. P. 54.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
30
STEHR, F. W., Editor. 1987. Immature Insects. Iowa: Kendall Publishing Company. P.
175.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
APPENDICES
Appendix Table 1. The total number of carabid beetles collected from the pitfall trap from August to October 2009
TRAP NUMBER
________________________________________________________________________________
FARMS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 TOTAL
Balili
0 0 0 0 0 0 0 0 0 0 0 0 1 3 1 1 0 0 0 0 0 0 0 0 0
6
Longlong 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
2
Swamp 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 1
4
TOTAL
0 0 0 0 0 1 0 0 0 0 0 0 1 3 2 1 0 0 0 0 0 0 0 3 1
12
______________________________________________________________________________________________________
31
Appendix Table 2. The total number of earwigs collected from the pitfall trap from August to October 2009
TRAP NUMBER
________________________________________________________________________________
FARMS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 TOTAL
______________________________________________________________________________________________________
Balili
0 0 0 0 0 0 0 0 0 1 1 0 8 2 0 1 0 0 0 0 0 0 0 0 0
13
Longlong 0 2 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 1
9
Swamp 0 4 1 1 0 5 0 0 1 0 0 1 1 0 0 0 0 0 0 0 0 0 1 0 0
15
TOTAL
0 6 1 1 0 9 0 0 1 1 1 1 9 2 0 1 0 0 0 0 0 0 1 2 1 37
______________________________________________________________________________________________________
32
33
Appendix Table 3. Total number of carabid beetles collected from the quadrant metal trap
from August to October 2009
===============================================================
TRAP NUMBER
__________________________________________________
FARMS
1 2 3 4 5 6 TOTAL
________________________________________________________________________
BALILI
0
0
0
0
1
1
2
LONGLONG
0
0
0
3
5
0
8
SWAMP
2
13
10
1
3
7
36
TOTAL
2
13
10
4
9
8
46
===============================================================
Appendix Table 4. Total number of earwigs collected from the quadrant metal trap
from August to October 2009
===============================================================
TRAP NUMBER
__________________________________________________
FARMS
1 2 3 4 5 6 TOTAL
________________________________________________________________________
BALILI
0
0
1
2
0
0
3
LONGLONG
6
0
2
1
5
1
15
SWAMP
3
13
12
5
2
1
36
TOTAL
9
13
15
8
7
2
54
===============================================================
PALADA, DENSON B. APRIL 2009. Occurrence of Carabid Beetles and
Earwigs in Strawberry Farms in La Trinidad, Benguet. Benguet State University, La
Trinidad, Benguet.
Adviser: Bonie S. Ligat, MSc
ABSTRACT
The study was conducted in three Strawberry farms in La Trinidad, Benguet from
August to October 2008. Improvised pitfall traps and quadrant metal were used to collect
insects once a week. The specimens were counted, identified and recorded. The study
aimed to to identify the species of Ground Beetles and Earwigs present in the farm, to
asses the population of Ground Beetles and Earwigs and to document the insects with the
use of Digital Camera.
Three (3) species of Carabid Beetles were collected: Chlaenius tricolor,
Bembidioni versicolor, and the Patrobus longicornis. There were also three species of
Earwigs: the Anisolabis maritima, Euborellia annulipes, and Forficula auricularia.
The population of carabid beetles in three months ranged from 12 to 46 while the
Earwigs ranged from 47 to 53.
TABLE OF CONTENTS
Pages
Bibliography………………………………………………………….…………. i
Abstract ………………………………………………………………….……… i
Tables of Contents………………………………………………………………. ii
INTRODUCTION……………………………………………………………… 1
REVIEW OF LITERATURE………………………………………….…….… 4
MATERIALS AND METHODS……………………………………………… 10
RESULTS AND DISCUSSION ……………………………………………… 18
Species of Carabid Beetles…………………….. ……………………… 18
Species of Earwigs……………………………………………………… 22
Other Insects…………………………………………………………… 26
SUMMARY, CONCLUSION AND RECOMMENDATION ……………… 27
Summary ……………………………………………………………… 27
Conclusion …………………………….……………………………… 27
Recommendation …………………………………………………….. 28
LITERATURE CITED………………………………………………………. 29
APPENDICES ………………………………………………………………. 31
ii
INTRODUCTION
The growing hazards that go along with the heavy use of chemicals to produce
man’s food and other basic commodities has enlightened the enthusiasm of many
institutions and workers to develop alternative measures to minimize the use of chemicals
in agricultural and industry. One of their objectives is to minimize the pollution of our
environment and its resultant effect on human health. The Philippine Council for
Agriculture, Forestry and Natural Resources Research and Development through its
Agricultural Resources Management Research Division, has already taken significant
strides.
President Gloria Macapagal Arroyo declared Executive Order 481, a state’s
policy to promote and develop Organic Agriculture in the country. on July 27, 2005
which is called the Organic Agriculture (OA) including all agricultural systems that
promote environmentally, socially, and economically sound production of food and
fibers. It sprang from the need to produce safe food as an alternative to alleviate over
exploitation and degradation of natural resources. Since then the policy was executed,
Benguet State University is now spearhead the Province of Benguet in promoting
Organic Agriculture especially in the Vegetable Industry.
In support to the institution’s program, research on different Organic practices
have been started and this including the use of biological control against pest such as
insect predators, parasitoids, and pathogens.
Beneficial insects like Carabid beetles and Earwigs/ predatory that feed on
immature pests. Carabidae is a large family with more than 40,000 species worldwide.
Most species are carnivorous, and some run swiftly to catch their prey. Although there is
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
2
a variation on their body shape and coloring, most are shiny, black, and have rigid elytra.
Gourd beetles in the genus Brachinus are commonly known as bombardier beetles;
ground beetles in the family Cicindelidae are known as tiger beetles. Unlike most
species of Carabidae, which are nocturnal, tiger beetles are active diurnal hunters, and
often brightly colored. All species except the primitive Paussinae, have a groove on their
front tibia bearing a comb hairs, for cleaning their antennae, common habitats are under
the bark of trees, under logs, or amongst rocks or sand by the edge of ponds and rivers
(Drees et al., 1999).
The earwig is one of the important insect because most earwigs feed on decaying
plant matter and some species are predatory and feed on a variety of other insects. They
can be easily identified by their forceps-like pincers (cerci), which they use for defense.
Many species are wingless and live in the soil or in enclosed spaces. Predatory earwig
will enter plant stems of stem boring and they are ussually hide during daytime and
become active at night.
Once Organic Farming becomes fully implemented in the country, Carabid
beetles, earwigs and other important insects will be conserved and reared in mass for
biological control against insect pests. It will also observe if the ground beetles
(Carabidae and Earwigs) are present in strawberry farms. Furthermore, it will provide a
benchmark data for future researchers who wish to study more on the different ground
insects in strawberry farms.
The study was conducted to Asses the population of ground beetles and earwigs
on strawberry farms in La Trinidad, Benguet; identify species of ground beetles and
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
3
earwigs and record other ground insects caught in the trap and encountered in the
Quadrant Metal.
The research concentrated on the occurrence of ground beetles and earwigs on
strawberry farms. This is because these insects are important predators that could be used
as biological control. The study was conducted in three areas of La Trinidad: Longlong,
Swamp area, and at the Entomology field located at Balili. The study was conducted from
August to 0ctober 2008.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
REVIEW OF LITERATURE
Carabid Beetles
Some soil coleopterans are predators of other soil animals, others are
Phytophagous. Include in the latter group are the well known larvae of scarabs and
chaffers which feed upon plant roots (Richards, 1974).
Biology
Larvae of some species are considered to mainly carnivorous and wide-
ranging, feeding on some soft-bodied insects. Euborellia annulipes (Lucas), the ring-
legged earwig has been recorded from beneath stones, debris or litter of various
kinds in compost heaps or dung in which it may be numerous, or in fruits, among
vegetation, or in houses (Stehr, 1987).
The ground beetles are predaceous, the prey consisting mainly of insects but
including also earthworms, snails, etc., though a few species are questionably
phytophagous and others at times partake of plant food in addition to insect diet. The
insect feeders attack lepidopterous larvae and naked pupae more generally than they
do the immature stages of other orders, though a number of species are recorded are
feeding extensively upon scarabeid grubs in the soil. The adults are predominantly
ground dwellers, and they carry their activities mainly at night. They may can be
found also in various protected locations, such as under stones and debris and the
loose bark of trees, or they may inhabit distinct burrows (Stehr, 1987).
The feeding habits of the adult beetles vary considerably from those of the
larvae. Thus, a number of species of Carabus, Craspedonotus, and other genera have
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
5
been recorded as attacking and feeding upon adult beetles, snails, etc. Calosoma
inquisitor L. of Europe is particularly abundant in areas bearing broad-leaved trees,
upon the foliage of which it searches for caterpillars. The variety of food consumed
by the adults is appreciably greater than that consumed by the larvae, partly owing to
their greater agility, enabling them to capture insects that can escape from the larvae.
Feeding may be very rapid, consisting of the biting or tearing away of portions of the
tissue of the victim after the integument has been broken, or it may solely by the
ingestion of liquid materials, resulting from the preoral digestion of the host tissues,
in addition to the body fluid (Clausen, 1962).
Carabid ground beetles go through egg, larval, and pupal stages of
development before reaching adulthood. Development from the egg to the adult stage
generally takes about a year. The adults of some species lay their eggs in specially
constructed mud or twig cells, while others lay their eggs in debris. Some adults may
live 2 to 3 years (Carey, 2005).
The Sidewalk Carabid a ground beetle has almost 2200 species in the United
States and throughout the world. The Sidewalk Carabid was chosen to represent the
family simply because it is the most commonly encountered species in residential
areas. These are good bugs. They feed on any kind of ground-inhabiting larvae and
insect eggs. They live in ground covers and in compost piles. In the garden they
prefer to eat cut worms, so gardeners love to see these beetles take up
residence. Ground beetles range in size from about 2 mm to 25 mm (1/8 inch to 1
inch). Most tend to be black, but there are a wide variety of colors represented in the
various species. Some are dark brown and sometimes have a bronze or green metallic
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
6
sheen. Sidewalk Carabid is shiny black and about 15 mm long. These are robust
beetles with proportionately large powerful jaws.Ground beetles are found
everywhere in the United States, Canada, and throughout the world. The Sidewalk
Carabid is largely restricted to the larger towns and cities, but has been gradually
working its way into the countryside. It is an introduced species, originally coming
from Europe (Maddison, 2006).
Ecology
Most carabids are omnivorous (feeding on both plants and animals) and
polyphagous (being able to use a wide range of foods), feeding on live prey, carrion
and plant material. Some species however are specialist feeders, i.e. Harpalus rufipes
(the Strawberry Seed Beetle) on seeds, Loricera pilicornis (the Springtail Beetle) on
Collembola and Abax parallelopipedus and Cychrus caraboides on slugs and snails.
Offonus species feed exclusively on the seeds of Umbellifers, this is known as
spermophagy. The larvae are always carnivorous if the adults are. Many Carabids
find their food by random foraging, but specialist feeders tend to use chemical cues.
Pterostichus cupreus has a two dimensional search pattern until it finds an aphid at
the base of a plant. Finding the aphid stimulates it to a three dimensional search
pattern, i.e. it climbs the plant looking for more aphids. Most species of Ground
beetles are cannibalistic given the opportunity. Abax parallelopipedus is unusual in
that it is not cannibalistic it can often be found under rotten logs in woodlands
(Anonymous, 2006).
Predacious ground beetles also referred to as carabids, belong to a large
family of beneficial beetles called the Carabidae. There are several thousand species
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
7
of these beetles in North America alone. The adult beetles range from 1/8-inch to 1¼
inches long. Variable in shape, they are usually elongate, heavy bodied, and slightly
or distinctly tapered at the head end while generally dark in color (dark brown to
black), some beetles are an attractive purple or metallic green, or are multi-colored, as
some case of some tropical species. Ground beetles are fast-moving insects, which
generally have prominent, long legs and fairly threadlike antennae. Most native
species to the area are found in the wetter regions (or around waterways). Larval
ground beetles are elongate and wormlike in appearance; most live in burrows in the
soil or in leaf litter or other debris. Both larval and adult ground beetles have
powerful and prominent mandibles. This is an adaptation for their predacious life
style. Most ground beetles in this area feed on a varied diet of insects and insect-like
creatures, many of which are garden or house pests, such as cutworms or house fly
maggots. One specific group of ground beetles feeds on snails and slugs. Some
occasionally feed on earthworms, but their beneficial feeding habits, in general, far
outweigh any detrimental effects they may have on local earthworm populations. A
few species will even feed on pollen or seeds. When carabids are disturbed they often
demonstrate some form of defensive behavior. Many northwestern native species
secrete chemicals that have a bad odor. This behavior is thought to be a deterrent to
animals which might eat them (Carey, 2005).
Dermaptera-Earwigs
Acccording to Alford (1999), Earwigs are polyphagous and are beneficial and
will destroy large numbers of Aphids and other pests. They are nocturnal insects, and
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
8
usually hide during the daytime amongst curled leaves, under loose bark and in other
sheltered situations.
Earwigs are medium-sized insects that superficially resemble certain types of
beetles. They are elongate insects with a pair of pincer-like cerci at the tip of the
abdomen. These insects may or may not have wings. Those with wings have front
wings that form short, leathery coverings for the large membranous hind wings.
Earwigs have chewing mouthparts and three-segmented tarsi and show little change
in body form during growth (Gradual metamorphosis). Some species with gland and
openings on the gland that emit a foul-smelling liquid believe to serve as protection
from enemies (Pedigo and Rice, 1989).
Earwigs are active at night and hide during the day. They feed mostly on
decaying organic matter, but few occasionally feed on plants, and others are
predaceous.
Earwigs as Pest Control
Earwigs can be considered in some ways as beneficial insect and part of the
garden, especially when they prey on other insects, but they can become a nuisance
because of their habit of positioning themselves within leaves and feeding on soft
plant tissues. They prefer cool, moist places, and a rolled up damp newspaper placed
where earwig activity is suspected can be effective in collecting them. The newspaper
can then either be discarded or shaken out. Placing diatomaceous earth in key spots
around the home (bathroom, baseboards, window frames) can be a long-term
repellent (Rankin and Palmer, 2003).
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
9
Hundreds of thousands of these beneficial predators are now being produced
and released in corn farms infested with asian corn borer, cutworm, corn earworm,
armyworm, grasshoppers, and semi-looper (Fernandez, 2008).
Cotton Development Authority (CODA) also developed a technology on the
use of earwigs against the flower weevil on cotton. The earwigs both the nymph and
adult feed on the larva and pupa of flower weevils. Their life span ranges from 82-
104 days. These predators are mass-reared and are released in the field when flower
weevils are present. Initial population of the predator can be collected from the soil
and shed young bolls. It can be mass-produced in the laboratory using larva of
Tribolium sp. or its hosts. Three-week old earwig nymphs and adults at 9,000 to
11,000 per hectare can be released at 68, 82 and 89 days after planting (DAP) or on
the first occurrence of flower weevil. The first release should coincide with the
hatching of the first generation of flower weevil eggs. The predation efficiency of
earwigs ranges from 20.44 to 23.15 percent. Using earwigs, seedcotton yield is
expected to increase by 19.15 to 22.18 percent (Anonymous, 2008).
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
MATERIALS AND METHODS
Materials
The materials used were; improvised pitfall traps (75 pieces) made of plastic
bottles with measuring about 8 cm diameter with 11 cm tall with plastic shade, 1
kilogram detergent tide powder, forceps, microwavable plastic container, camera,
microscope, and one quadrant metal trap made up of tin can (27 X 27 X17 cm), and
improvised sieve.
Methodology
Location. The study was conducted in th three strawberry farms in La Trinidad,
Benguet measuring 500 sq m each particularly at the Entomology field located at Balili
(Figure 1), Longlong (Figure 2), an Swamp area (Figure 3). The Strawberry plants in
Balili are at their senescence stage, at Longlong the strawberry were bearing fruits while
at Swamp the strawberry are on their vegetative stage.
Pit
trap. An improvised pitfall trap was prepared using empty C2 plastic bottle
and used as shown in figure 4ab. The plastic trap was half-filled with water mixed with
tide detergent. The detergent was used as a repellant. Twenty five traps at each farm site
were arranged in transect (Figure 5). Each trap was put in a dug as shown in Figure 6. it
filled with water and the tip was elevated at least ½ inch above the ground. The traps
were provided with plastic shade against rain (Figure 4a) with 1 ½ distance from the
ground. The introduced pitfall traps were carefully observed one after it was introduced
and every week thereafter for 12 weeks. The water-detergent container was replenished
when necessary to keep the trapped insects in place prior to collection period. In
collecting the insects, the traps were decanted and sieved (Figure 8c).
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
11
Figure 1. The site at Balili with dry cogon grass as mulch
Figure 2. The site at Swamp with Polyethylene mulch
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
12
Figure 3.The site at Longlong with polyethylene as mulch
a
b
Figure 4. Improvised Pitfall trap cover. a.) Top view and b.) Side view
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
13
Figure 5. TheTransect Method
Figure 6. Top view of a Pitfall trap set up beside a Strawberry plant
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
14
Quadrant metal trap. Insects tend to hide during the day and they may forage in
the weeds outside the area. The quadrant metal was used to determine insects also outside
the experimental area. Hence, a quadrant metal trap (Figure 7) was improvised and used.
The quadrant metal trap was set up by pressing the side surface in areas outside the
strawberry fields where there are grasses. The area inside the trap was cleaned by
uprooting all the grasses. Samples of isects present inside the trap were gathered and
recorded. Afterwhich the grasses were removed and exposed the earwigs and Carabid
beetles that are ussually soil-bone.
The insects were gathered using forceps (Figure 8) and through an improvised
sieve. Insects were documented using Digital Camera with a white Background through a
microscope (Figure 9 & 10). Identification book and microscope were used to identify the
insects at the Mite Predators Rearing House ( Figure 11).
a
b
Figure 7. Quadrant metal trap. a.) Side view b.) top view
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
15
a
b
c
Figure 8. Materials used in the collection of specimens. a.) microwavable plastic,
b.) forceps, and c.) improvised sieve.
a
b
Figure 9. Materials used in identifying the specimens. a Microscope, and
b) identification book
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
16
Figure 10.The researcher identifying the collected insects.
Figure 11. The mite predator rearing house
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
17
The data gathered were:
1. Number of adult carabid beetles and earwigs.This is to determine the species and the
population of these insects in the three samplimg sites.
3. Photographs of insects collected. These were that were caught in the trap.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
RESULTS AND DISCUSSION
Carabid Beetles
Pit trap
Species. The monitored species of Carabid beetles that were collected are
presented in Table 1. There are three species as follows: Chlaenius tricolor (Figure 12),
Bembidioni versicolor (Figure 13), and Patrobus longicornis (Figure 14).
Population. There were eight adults of Chlaenius tricolor, four were collected
from Balili and also four from Swamp while it was absent in Longlong. Only one
Bembidioni versicolor was collected from Balili while it was absent from the two sites. In
terms Patrobus longicornis, one was collected from Balili, two from Longlong, and was absent
at the Swamp area.
Bembidioni versicolor was the least in number while Chlaenius tricolor has the
highest in number. The differenmce could be due to the observation that Bembidioni
versicolor stay at the side of the strawberry plots where the polyethylene mulch ends.
Thus, these were not caught at the pitfall traps that were situated at the strawberry plots.
Chlaenius tricolor on the other hand, was absent in Longlong. According to
Murray (2007), their habitat is usually moist areas, some and some are semiaquatic and
the site at Longlong was a little bit dry and elevated.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
19
Chlaenius tricolor. It measures 8-23 mm
in Size. Medium sized to large ground beetles.
They are Attractive, often with vivid metallic
coloration of head. Pronotum has distinctive
indentations. Head, pronotum, and elytra have
fine hairs (“setose”setae). front tarsomeres
1-3 of male are dilated, have spongy underside
Figure 14. Chlaenius tricolor (Murray) presumably used in mating. The covered
.
with hairs that lie flat.
Bembidioni versicolor. This has some
distinguishing characteristics that include elytra;
pronotum with relatively dull luster and
lateral margins parallel toward base.
Figure 15. Bembidioni versicolor (Murray)
Patrobus longicornis. It is the almost
the same with Bembidioni, the difference is the
long antennae and the color pure black color of
its body.
Figure 16. Patrobus longicornis (Eaton)
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
20
Table 1. Total population of carabid beetles species collected from the pitfall trap from
August to October 2009
===============================================================
SPECIES POPULATION
__________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
4
0
4
8
Bembidioni versicolor
1
0
0
1
Patrobus longicornis
1
2
0
3
TOTAL
6
2
4
12
===============================================================
Quadrant Metal Trap
Species. In this trap the species collected were similar to those trapped from the
pitfall.
There were Forty six (46) individuals of Carabid beetles from the three (3)
species. The highest in number was the Bembidioni versicolor which was gathered from
Longlong and Swamp while this was absent at Balili. Patrobus longicornis has seventeen
and it was gathered from the three sites. Chlaenius tricolor was not present neither from
the three sites.
There was no collected Chlaenius tricolor from the three sites. They may be
present in the side areas of the sites but the Quadrant Metal Method was done only once
in a month having the tendency that they were not encountered. Bembidioni versicolor is
absent in Balili this could be because the side areas was being disturbed by the
neighboring Garden prior to the removal of the grasses. On the other hand, they were
abundant in Swamp because the sides of the area were filled with different waste that
attracted other insects including larvae. These insects served as food for the Bembidioni
versicolor. Patrobus longicornis was encountered in the three sites
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
21
Table 2. Total population of carabid beetles encountered from the quadrant metal from
August to October 2009
===============================================================
SPECIES POPULATION
___________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
0
0
0
0
Bembidioni versicolor
0
6
23 29
Patrobus longicornis
2
2
13 17
TOTAL
2
8
36 46
===============================================================
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
22
Earwigs
Pitfall trap
Species. The collected species of Earwigs were the following: Anisolabis
maritima (Figure 15) Euborellia annulipes (Figure 16), and Forficula auricularia (Figure
17).
Population. In Balili, there were thirteen earwigs collected from the pitfall trap.
There were four Euborellia annulipes, nine Forficula auricularia and no Anisolabis
maritima were collected. There were also nineteen Earwigs collected in longlong, three
were Anisolabis maritima species, three Euborellia annulipes, and thirteen Forficula
auricularia. The three species were also present in Longlong, three Anisolabis maritima,
six Euborellia annulipes and six Forficula auricularia were collected. To sum it up there
were forty seven Earwigs collected from the whole duration of the implementation as of
August to October, 2008.
There were no caught Anisolabis maritima in the improvised pitfall trap from the
whole duration of the study in Balili. The reason could be the senescence stage of the
strawberry plant that affected the absence of the species. There were at least thirteen
collected Euborellia annulipes species from the three sites. Forficularia auricularia on
the other hand is also present in the three sites. They were abundant in Longlong maybe
because the place is suited them.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
23
Euborellia annulipes. Its size is
12-18 mm. They are medium-sized
dark-brown earwig with dark areas on
the light-yellow
legs ("black
armbands"). The species is wingless.
Adults have antennae with 14-16 the
third and fourth segments, (sometimes
Figure 15. Euborellia annulipes (Eaton) the fifth) from the end being white or
pale.
Forficula auricularia. Body
length ranges from 12 to 15 mm. Male
forceps 4 to 8 mm (Figs. 1-2); female
forceps 3 mm, tegmina 2 mm. Male
Figure 16. Forficularia auricularia (Murray) forceps vary from about half as long to
longer than the abdomen, broadened
basally, with crenulate teeth basally and
on beginning of curvature of inner
margin. Antennae hhave 14 or 15
segments. The adult is rich reddish-
brown, with wing covers and legs dull
yellow
brown, and the wings
completely developed.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
24
Anisolabis maritime. Wingless
form earwig with a medium-sized body.
Antenna with no white antenna
segment.
Figure 17. Annisolabis maritime (Eaton)
Table 3. Total population of earwig species collected from the pitfall trap from August
to October 2008
===============================================================
SPECIES POPULATION
___________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
0
3
3
6
Bembidioni versicolor
4
3
6
13
Patrobus longicornis
9
13
6
28
TOTAL 13
19
15
47
===============================================================
Quadrant Metal
Species. the species that were collected in this trap were similar to thew species
collected from the pitfall trap. They were the Anisolabis maritima, Euborellia annulipes
and Forficula auricularia
Population. Three Earwigs were collected from Balili, there is no Anisolabis
maritime, one Euborellia annulipes and two Forficula auricularia. fifteen individuals
were also collected from Longlong three Anisolabis maritime, four were Euborellia
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
25
annulipes and eight were Forficula auricularia.in. Swamp Area, there were thirty five
earwigs collected as follows: six Anisolabis maritima, six Euborellia annulipes and
twenty three Forficula auricularia. The Collected Earwigs has a total number of fifty
three of all the species collected, Forficula auricularia has the highest in number, having
a total number of thirty three, while there eleven and nine individuals for the Anisolabis
maritima and Euborellia annulipes respectively.
The same in the Pitfall trap, there were no encountered species of Anisolabis
maritima at Balili the reason could be they are absent in the area. Euborellia annulipes
and Forficula auricularia were also present in the three sites. In terms of the collected
individuals of the species, Balili got the lowest count. This could be affected by the
situation of the area wherein there were no grasses found at the side of the farm.
Table 4.Total population of earwigs species collected from the quadrant metal from
August to October 2008
===============================================================
SPECIES POPULATION
___________________________________________________
BALILI LONGLONG SWAMP TOTAL
_______________________________________________________________________
Chlaenius tricolor
0
3
6
9
Bembidioni versicolor
1
4
6
11
Patrobus longicornis
2
8
23
33
TOTAL
3
15
35
53
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
26
Other Collected insects
Aside from the Earwigs and the Ground Beetles there were other collected insects
through the two methods from the three sites. These were the Ants, thrips, Cockroach,
Cricket, Dung Beetle, Housefly, Katydid, Lady Bug Beetle, Rove Beetle, and Snout
Beetle. Lady Bug Beetles and Rove beetles were known as insect predators/Beneficial
insects that were found. Lady Bug Beetles was collected from Balili while the Rove
Beetles were collected from from Longlong.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
SUMMARY, CONCLUSION AND RECOMMENDATION
Summary
The study was conducted at La Trinidad, Benguet from August to October, 2008
to assess the population of Ground Beetles and Earwigs, identify their species and record
other ground insects within the strawberry farms in La Trinidad, Benguet.
Three farms in La Trinidad, Benguet were established as collection sites.
Improvised pitfall trap and Quadrant Metal were used to collect insects. After collecting
species of insects, it was recorded and quantified. Gatherigns of Samples was done
weekly for the pitfall trap and once in a month for the Quadrant metal.
There were three species of carabid beetles collected from the three sites, the
Chlaenius tricolor, Bembidioni versicolor, and the Patrobus longicornis. There were also
three species of earwigs, the Anisolabis maritima, Euborellia annulipes, and Forficula
auricularia. Other insects also that were recorded were as follows: Ants, Thrips,
Cockroach, Cricket, Dung Beetle, Housefly, Katydid, Lady Bug Beetle, Rove Beetle, and
Snout Beetle. There were five insects belonging to the Order Coleoptera, two insects
belong to the Order Orthoptera, one insect also belong to Order Hymenoptera one and
one also from the order Blattodea.
Lady Bug Beetles and Rove beetles were known as insect predators/Beneficial
insects that were found. Lady Bug Beetles was collected from Balili while the Rove
Beetles were collected from Longlong.
Conclusion
There were Carabid Beetles and Earwigs in Strawberry farms in La Trinidad,
Benguet. There were three species of Carabid beetles (Claenius tricolor, Bembidioni
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
28
versicolor and, Patrobus longicornis). Earwigs were also present in the areas, there were
three species found from the three areas namely: Forficularia auricularia, Annisolabis
maritima and Euborellia annulipes.
The Ecological Society of America (ESA) concluded that the larval diets of
carabid beetles are carnivorous in general, and are divided into three types: insect larva
feeder (feed on lepidopteran and dipteran larvae), snail feeder and earthworm feeder.
Adult beetles of these three types tend to be omnivorous. While Hadley (2008) mentioned
that the earwig’s diet is highly variable. European earwigs feed at night on the foliage of
various flowers and garden plants. Most species prey on other insects and supplement
their diet with decaying organic matter found in soil or garbage. In addition to consuming
aphids, beetle larvae, and maggots.
With the presence of these important predators, the researcher concluded that the
three sites at Balili, Longlong and Swamp area are still good. We should conserve these
insects, as they are important that will help us control the insect pest in our farms.
Recommendation
It is recommended that further study more on Carabid Beetles and Earwigs should
be done for 1 year to know their activities, during summer, when there is typhoon or
heavy rain.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
LITERATURE CITED
ALFORD, D. V. 1999. A Textbook of Agricultural Entomology. 10 rue Casimir
Delavigne
75006, Paris, France. Blackwell Science Ltd. P. 59.
ANONYMOUS. 2008. Flowerweevil Control Without Chemical Pesticide. Retrieved
March 2, 2009 from http://coda.da.gov.ph/archives/flowerweevil_control.php
ANONYMOUS. 2006. Carabid Beetles. Retrieved July 8, 2008 from
http://www.earthlife.net/insects/carabids.html
CAREY, B. 2005. The Carabid Beetles. Retrieved July 10, 2008 from
http://gardening.wsu.edu/library/inse002/inse002.htm
CLAUSEN, C. P. 1962. Entomophagous Insects. USA, New York. Hafner Publishing
Company. Pp 528-529.
DREES, B. M. and J. JACKMAN. 1999. Field guide to Texas insects. Houston.
Retrieved May 20, 2008 from http://www.insects_beetles/Carabids/Article.html.
ECOLOGICAL SOCIETY OF AMERICA (ESA). 2005. Poster Session 30: Invertebrate
Ecology. Retrieved March 23, 2009 from
http://abstracts.co.allenpress.com/pweb/esa2005/document/49879.
FERNANDEZ, R. A. 2008. Earwig: Guardian of Ilocos corn farms . Retrieved February
28, 2009 from http://www.philstar.com/Article.aspx?articleid=411906
MADDISON, D. R. 2006. Carabid Beetles. Retrieved July 8, 2008 from
http://www.eduwebs.org/bugs/ground_beetles.htm
MURRAY, T. 2007. Carabid Information. Retrieved March 23, 2009 from
http://bugguide.net/node/view/14055
HADLEY, D. 2008. More about Earwigs. Retrieved March 23, 2009 from
http://insects.about.com/od/beetles/p/carabidae.htm
PEDIGO, L. P. and M. E. RICE. 1989. Entomology and Pest Management. Upper Saddle
River, New Jersey, Columbus, Ohio. Pearson Prentice Hall.
RANKIN, S. M. and J. O. PALMER. 2003. .http://en.wikipedia.org/wiki/Earwig#Pest
control
RICHARDS, B. N. 1974. Introduction to Soil Ecosystem. USA, New York. Longman
Group Limited. P. 54.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
30
STEHR, F. W., Editor. 1987. Immature Insects. Iowa: Kendall Publishing Company. P.
175.
Occurrence of Carabid Beetles and Earwigs in Strawberry Farms
in La Trinidad, Benguet / Denso B. Palada. 2009
APPENDICES
Appendix Table 1. The total number of carabid beetles collected from the pitfall trap from August to October 2009
TRAP NUMBER
________________________________________________________________________________
FARMS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 TOTAL
Balili
0 0 0 0 0 0 0 0 0 0 0 0 1 3 1 1 0 0 0 0 0 0 0 0 0
6
Longlong 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
2
Swamp 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 1
4
TOTAL
0 0 0 0 0 1 0 0 0 0 0 0 1 3 2 1 0 0 0 0 0 0 0 3 1
12
______________________________________________________________________________________________________
31
Appendix Table 2. The total number of earwigs collected from the pitfall trap from August to October 2009
TRAP NUMBER
________________________________________________________________________________
FARMS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 TOTAL
______________________________________________________________________________________________________
Balili
0 0 0 0 0 0 0 0 0 1 1 0 8 2 0 1 0 0 0 0 0 0 0 0 0
13
Longlong 0 2 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 1
9
Swamp 0 4 1 1 0 5 0 0 1 0 0 1 1 0 0 0 0 0 0 0 0 0 1 0 0
15
TOTAL
0 6 1 1 0 9 0 0 1 1 1 1 9 2 0 1 0 0 0 0 0 0 1 2 1 37
______________________________________________________________________________________________________
32
33
Appendix Table 3. Total number of carabid beetles collected from the quadrant metal trap
from August to October 2009
===============================================================
TRAP NUMBER
__________________________________________________
FARMS
1 2 3 4 5 6 TOTAL
________________________________________________________________________
BALILI
0
0
0
0
1
1
2
LONGLONG
0
0
0
3
5
0
8
SWAMP
2
13
10
1
3
7
36
TOTAL
2
13
10
4
9
8
46
===============================================================
Appendix Table 4. Total number of earwigs collected from the quadrant metal trap
from August to October 2009
===============================================================
TRAP NUMBER
__________________________________________________
FARMS
1 2 3 4 5 6 TOTAL
________________________________________________________________________
BALILI
0
0
1
2
0
0
3
LONGLONG
6
0
2
1
5
1
15
SWAMP
3
13
12
5
2
1
36
TOTAL
9
13
15
8
7
2
54
===============================================================
Document Outline
- Occurrence of Carabid Beetles andEarwigs in Strawberry Farms in La Trinidad, Benguet
- BIBLIOGRAPHY
- ABSTRACT
- TABLE OF CONTENTS
- INTRODUCTION
- REVIEW OF LITERATURE
- MATERIALS AND METHODS
- RESULTS AND DISCUSSION
- Carabid Beetles
- Earwigs
- SUMMARY, CONCLUSION AND RECOMMENDATION
- LITERATURE CITED
- APPENDICES