Proceedings of the 63rdAnnual Meeting of the
Acadian Entomological Society
in conjunction with the
Maine Entomological Society
June 22-24, 2003 at
College of the Atlantic, Bar Harbor, Maine
Sunday, June 22nd, 2002
Monday, June 23rd, 2003
Tuesday, June 24th, 2003
Arthropods of Medical Significance
Ticks of medical importance of Maine. Lacombe, Eleanor1, Richard Dearborn2, Mary S. Holman1, Charles Lubelczyk1, Peter W. Rand1, and Robert P. Smith1. 1MMCRI Vector Borne Disease Laboratory, 13 Charles St., 3rd floor, Portland, ME 04102 and 2Maine Forest Service, Entomology Lab, 50 Hospital Street Augusta, ME 04330.
The vector of Lyme disease, Ixodes scapularis, and Borrelia burgdorferi, the infective organism, were first reported in Maine from Bar Harbor in 1986. After determining in 1988 that Ixodes scapularis was established at at least two southern Maine coastal sites, the MMCRI laboratory and the Maine Deptartment of Conservation Insect and Disease Laboratory collaborated in offering a free tick submission program for hospitals, physicians, veterinarians, and the general public. Submissions of Ixodes cookei, the woodchuck tick, which closely resembles I.scapularis, and is widely distributed in Maine have remained stable over this fourteen year period, but submissions of I. scapularis have increased 6-fold and 30-fold in coastal and inland regions, respectively. This increase has been paralleled by the number of Lyme disease cases reported to the Maine Bureau of Health.
Both I. scapularis ticks containing
the infective organisms and human cases of HGE and babesiosis also have
been found, although numbers remain small. At least eleven other species
of ticks are found in Maine. Incidentally, this program has also provided
information about other ticks of medical and veterinary importance. In the
last two years three human cases of the encephalitis causing Powassan
virus have been recognized. Implicated vectors are Ixodes cookei
and possibly I. marxi,as well as I.scapularis,but much
remains to be learned about the extent and distribution of this virus.
Other species of ticks, including I. muris which causes an acute
reaction at the time of the bite, will be discussed.
Habitat associations of Ixodes scapularis, the vector of Lyme disease, in Maine. Lubelczyk, Charles, Susan P. Elias, Peter W. Rand, Mary S. Holman, Eleanor H. Lacombe, and Robert P. Smith, Jr. MMCRI Vector Borne Disease Laboratory, 13 Charles St., 3rd floor, Portland, ME 04102.
We assessed the association of habitat
features with the presence of questing adult Ixodes scapularis
Say (= I. dammini Spielman, Clifford, Piesman &
Corwin) at three sites in coastal Maine from 1998-2000. Using
multivariable logistic regression, ticks were found to be more likely in
the presence of a shrub layer, deciduous seedlings, mature forest,
grasses, or moist-soil ferns and less likely in the presence of coniferous
litter. In a second model that related I. scapularis presence to
the shrub species, Japanese barberry Berberis thunbergii DC,
winterberry holly Ilex verticillata Linnaeus (Gray), high-bush
blueberry Vaccinium corymbosum L., and Eurasian honeysuckles
Lonicera L. were associated with tick presence. We also used
multiple correspondence analysis to visualize relationships of significant
habitat variables to tick presence. Multiple correspondence analysis
grouped I. scapularis with a dense shrub layer, deciduous litter
and ground cover, grasses and specifically, barberry, honeysuckle, holly,
high-bush blueberry, and moist-soil ferns Osmunda sp. L. and
Onoclea sensibilis L. Absence of ticks was associated with open
understory, coniferous litter, and dryer soils. Natural resource managers
should be aware that landscape changes, including alteration of plant
communties by deer browsing, might create favorable tick habitat. These
findings could prove helpful in assessing local risk of Lyme
Mosquitoes and West Nile Virus (WNV) in Maine. Foss, Kimberly and Richard Dearborn. Maine Forest Service, Entomology Lab, 50 Hospital Street Augusta, ME 04330.
The introduction of West Nile Virus in the New
York area during 1999 prompted mosquito surveillance protocols throughout
the Northeast. Studies were initiated in Portland, Bangor and coastal
southwestern Maine in 2001 to identify mosquito species and locate
potential breeding sites. By September of 2001, four birds collected from
various Maine areas tested positive for the virus. One crow from Sabattus
prompted another mosquito survey in the greater Lewiston, Auburn and
Sabattus area during 2002. The combined surveys provided important
information about native and introduced exotic mosquito species occurring
in Maine, the larval habitats of WNV vector species, as well as helped to
determine the seasonality of these important vector species.
Mosquito surveys and West Nile Virus (WNV) in New Brunswick. Webster, Reginald and Marie-Andrée Giguère. Entomology ConsultantS, 24 Millstream Drive, Charters Settlement, N.B. E3C 1X1, Canada.
Rising concerns that the WNV will eventually
become established in New Brunswick has led to an increased awareness of
the role mosquitoes play as vectors of this arbovirus. In view of this, a
preliminary survey of mosquitoes was conducted in the Fredericton area
during 2002. Protocols for sampling and monitoring mosquito populations
were developed, personnel capable of conducting future surveys were
trained, and information on the seasonal abundance and breeding habitats
of mosquitoes in the Fredericton area were obtained. Twenty-nine species
of mosquitoes were captured in CDC miniature light traps using CO2
at 6 sites during the five month sampling period. Twelve of these
are potential WNV vector species. Five of the 29 species were not
previously recorded from N.B. Sufficient numbers of adults were captured
to obtain data on seasonal abundance for most species. Seventeen species
of mosquitoes were collected as larvae and information was obtained on
breeding sites of 9 of the potential WNV vectors species. Between 21 and
27 species of mosquitoes were caught at each of the 6 sites. Although the
relative individual abundance of the species varied between sites, a
significant proportion of the total number of species was captured at each
site. This suggests that sampling only 2 sites with different wetland
types may be sufficient to obtain a significant proportion of the species
of mosquito species in a given region. During 2003 the mosquito survey is
being expanding to cover the entire province. Nineteen sites are being
sampled with 2-5 sites in each of the 7 health regions.
Movement of blueberry maggot fly within and between fields. Drummond, Francis. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469.
The blueberry maggot fly, Rhagoletis
mendax Curran, is a native tephritid which parasitizes the fruit of
huckleberry and many species of Vaccinium that are referred to as
blueberry. This fly is the major insect pest of lowbush blueberry
commercially produced in Maine. It overwinters in fields yielding fruit
and then because most blueberry fields are pruned after harvest and are
only vegetative the following year, the emerging flies must move to find
fruiting fields. Using a combination of emergence traps and yellow sticky
traps (Pherocon AMF®) we have found that the residence time of flies in
vegetative fields is variable from year to year and field to field. As
flies colonize fruiting fields they appear to fly low to the ground and
settle as they encounter the field edge. Mark-recapture studies have shown
that once within the field, movement is random in direction and averages
less than 10 m / day. Computer simulation and trapping studies in the
field suggests that this random movement results in the majority of flies
occurring near the field edge with fly density dropping off geometrically
towards the middle of the field. Within field movement is also
characterized by flights below 1.5 m above the crop canopy. Blueberry
maggot fly movement can mostly be studied as a two-dimensional diffusion
process, however, we have found that adult flies move vertically 15 m or
more up into the canopy of trees surrounding blueberry fields. The reason
for this vertical movement is not known, but it may have implications for
field perimeter based management strategies.
Effect of odor-bait composition, cultivar type, and adjacent habitat on the performance of perimeter traps for behavioral control of apple maggot fly. Hoffmann, Sara and Ronald Prokopy. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469 and Department of Entomology, Fernald Hall, University of Massachusetts, Amherst, MA 01003.
Behavioral control of apple maggot flies,
Rhagoletis pomonella, in eastern North America has traditionally
relied upon sticky-coated red sphere traps placed around the perimeter of
apple orchards and baited with the attractive apple odor, butyl hexanoate
(BH). In these studies we evaluated perimeter traps baited with a new,
highly attractive odor blend and a reduced concentration of BH (25%) for
effectiveness in preventing apple maggot flies from penetrating through
perimeter-row traps into the interiors of orchard blocks. We also examined
the effect of apple cultivar type (cultivars that were relatively
susceptible or tolerant to apple maggot flies) and the habitat adjacent to
the perimeter row (woods, hedgerow, or an open field) on trap efficacy.
Trap performance was measured by counting both wild and marked-released
flies captured by baited, perimeter-row traps and unbaited, interior-row
Synthetic host volatiles increase efficacy of trap cropping for management of Colorado potato beetle, Leptinotarsa decemlineata (Say). Martel, John1, A. Randall Alford1, and Joseph C. Dickens2. 1Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469 and 2Plant Sciences Institute, Chemicals Affecting Insect Behavior Laboratory, Beltsville, Maryland 20705.
The attractiveness of synthetic host volatile
attractant-baited pitfall traps and trap crops to colonizing adult
Colorado potato beetle, Leptinotarsa decemlineata (Say), and its
application to a comprehensive trap crop pest management strategy were
evaluated in a field setting. There were significantly more adult L.
decemlineata in baited than un-baited pitfall traps and significantly
more colonizing adults, egg masses, and small larvae in attractant-treated
trap crops than in untreated trap crops. There were no significant
differences in egg mass and small larvae densities between plots bordered
by attractant-treated trap crops and conventionally-managed plots, but
there were significantly fewer large larvae and adult beetles in
conventionally-managed plots than in plots bordered by untreated and
attractant-treated trap crops. Significantly less insecticide was applied
to plots bordered by attractant-treated trap crops than
conventionally-managed plots. Total insecticide input volume for plots and
associated trap crops was 44% less than for conventionally-managed plots.
Leaf Area Index (LAI) of conventionally-managed plots was significantly
higher than for plots bordered by either type of trap crop. However, there
was no significant difference in yield between conventionally-managed
plots and plots bordered by attractant-treated trap crops, therefore the
differences in insect density and LAI were not consequential to potato
production. The addition of the synthetic host attractant clearly
augmented the efficacy of otherwise untreated trap crops, with specific
regard to insect management and potato production
Functional morphology of the spider mite gnathosoma. Crooker, Allen and Rebecca Moffitt. Biology Department, Hartwick College, Oneonta, NY 13820.
The gnathosoma is the anteriormost portion of the acarine body. It comprises the mouthparts and related structures that assist in obtaining and transporting food to the digestive tract. The dorsum of the primitive or generalized gnathosoma is formed by the epistome; the lateral walls are formed by the pedipalpal coxae. The floor (infracapitulum) of the generalized gnathosoma is a fusion and extension of the ventral portions of the pedipalpal coxae. Paired chelicerae with fixed and moveable digits are present above the medial buccal cavity that opens into the pharynx.
The gnathosoma of spider mites is highly evolved and is adapted for plant feeding. The conventional epistome is lacking. The three articles of the chelicerae are greatly modified: the proximal joints form a bulbous, moveable stylophore, the fixed digits are slender, medial projections distal to the stylophore, and the moveable digits are elongate stylets that pierce plant tissues. The infracapitulum is a beak-like structure containing the pharynx and mouth. The apex of the infracapitulum possesses mouth lobes and a small orifice is present on its ventral surface. The palps are chemo- and mechanosensory appendages that aid the mite in locating food; the palps may also be used to mince food. Salivary glands located in the adjacent idiosoma empty into the buccal cavity via ducts.
During feeding, spider mites often adopt an
inclined posture with the rear portion of the body elevated and the
anterior regions supported by the infracapitulum and the first two pairs
of legs. The stylophore is moved toward plant tissue by muscular action,
then protractor muscles inserted on the base of the cheliceral stylets act
to provide the force needed for stylet penetration. The stylets interlock
to form a tube that may convey saliva to the feeding puncture. The mouth
lobes at the tip of the infracapitulum provide a seal around the stylets.
The seal likely permits utilization of the vacuum produced by the
pharyngeal pump, enabling the pump to suck plant juices into the digestive
tract. The infracapitular orifice opens into a short canal that leads into
the esophagus; the orifice and canal may act as a relief valve to help the
mite avoid injury due to excess plant fluid pressure.
What's 'bugging' our schools? Integrated Pest Management for schools and other 'sensitive' environments. Murray, Kathy. Maine Department of Agriculture, Food, and Rural Resources, 28 State House Station, Augusta, ME 04333.
In the past decade there has been increased recognition and public concern with risks of human exposure to pesticides, especially by children. The US National Academy of Sciences 1993 report entitled 'Pesticides in the Diets of Infants and Children' led to adoption by the US Congress of the 1996 Food Quality Protection Act. Schools in many US states and some Canadian cities are now encouraged, if not required, to adopt integrated pest management (IPM) programs aimed at reducing risks of environmental pesticide exposure in schools. This is a challenge for rural schools where professional expertise for structural, turf and landscape IPM are often scarce or unaffordable.
To determine pest concerns and pesticide use
patterns in Maine public schools, a mail survey was conducted. Survey
results indicated that most Maine schools do not use IPM, many apply
pesticides on a regular basis, and very few have any pesticide or pest
management policies. A tri-state program in northern New England was
established to provide training and support for schools to adopt IPM.
Implementers at key pilot demonstration sites are trained via live and
televised workshops. Training materials are provided at workshops and
through a website. The program is extended to other school districts via
'Open House' events. In addition, structural IPM training was provided to
health inspectors, education officials, non-profit organizations,
cooperative extension personnel, and other interested people who now serve
as 'para professionals' to assist schools in implementing IPM. School
inspections and questionnaires will be use to assess program
Ground beetle communities in mature forest, forest remnants, and harvest areas in western Maine. Whitman, Andrew and Charlene Donahue. Manomet Center for Conservation Science, 14 Maine Street, Suite 404 Brunswick, ME 04011 and Maine Forest Service, Entomology Lab, 50 Hospital Street Augusta, ME 04330.
Ground beetle communities in buffer strips left between clearcut areas, mature forests over 90 years old and 10 year old clearcut areas were sampled to determine if there were differences between the three types of treatment. Pitfall traps were arrayed along a transect with the three traps in each plot spaced 20 meters apart. Transects in the buffer strips ran from the edge of the buffer to the interior. Traps were set out during June and July of 2001 and 2002 and checked weekly.
Both forest and buffer plots averaged 11
forest ground beetle species. Clearcut plots had fewer forest species but
significantly more open habitat species then the forest and buffer plots.
Overall species richness was similar across treatments with clearcuts
having more open habitat species and forests and buffers having more
forest species. Forty-five different ground beetle species were captured
over the course of this study. Statistical analysis did not show any trend
from edge to interior of the buffer. These 10 year old buffer strips
appear to be serving as refugia for most forest ground beetles that are
much less abundant in clearcuts.
Short and long term effects of clearcut timber harvesting and glyphosate application on parasitic Hymenoptera in Maine. Abell, Kristopher and Stephen A. Woods. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469.
Parasitoids play an important role as natural
enemies of pest insects and contribute substantially to world
biodiversity, yet they have received relatively little attention outside
of agricultural settings. Clearcut harvesting and herbicide application
are frequent and widespread disturbances in Maine forests that drastically
alter the local environment. Parasitoids are particularly susceptible to
disturbance for several reasons: 1) they are vulnerable to small changes
in environmental conditions; 2) they occupy a high trophic level, and 3)
they are host specific. However, there may be potential benefits of
disturbance such as increased food resources (floral nectaries) and
increased abundance and diversity of hosts. To investigate the effects of
clearcut timber harvesting and herbicide application on parasitoids this
study looked at 18 sites in Maine managed by Plum Creek Timber Company.
Twelve sites were clearcuts; half were young (cut 3-5 years prior to
study) and half older (cut 15-16 years prior to study). Half of each age
group was treated with herbicide. Three mature forests not treated with
herbicide were used as controls. The remaining three sites were
plantations (cut 15-16 years prior to study, herbicide treated, and
planted with black spruce). Sites ranged in size from 0.2-3 ha. Samples
were collected every two weeks from June to August in 2000 and 2001 using
malaise and flight intercept traps. All parasitoids collected were
identified to family. To investigate a possible correlation between floral
resources and parasitoid abundance, floral density and diversity were
estimated at each site by four 40m transects. Preliminary analysis was
only conducted on malaise trap samples. In 2001 there was decreased
parasitoid abundance in old herbicide treated sites vs. old untreated
sites (p < 0.055). However, there was no significant
difference in parasitoid abundance between young treated and untreated
sites. Parasitoid abundance in plantations was significantly greater than
all other treatment groups (p < 0.0001). Parasitoid abundance
in old sites was significantly greater than in both young and mature sites
(p < 0.0001), which were not significantly different from each
other. Parasitoid abundance was weakly correlated (p < 0.1)
with floral density.
The effects of clearcut harvest and herbicide treatments on flowering plant and wingless wasp communities. Woods, S., K. Georgitis, and A. Cyr. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469.
A study was conducted on timberland owned and
operated by Plum Creek Timber Company of Fairfield, ME. The objectives
were to evaluate the short-term and longer-term influence of clearcut
harvesting and herbicide applications on communities of flowering plants
and insects. Twenty sites, representing six treatment groups, in the
vicinity of Bingham, ME were visited every other week from June through
August of 2000. Four pitfall traps were deployed at each of the sites with
samples being collected and returned to the lab on each visit. Samples
were subsequently sorted and wingless parasitic Hymenoptera were isolated
and sorted into morphologically distinct groups. An estimate of floral
densities was also obtained on each visit throughout the summer using
line-transect sampling. Only flowering plants in contact with the vertical
plane defined by four 40 m lines were included in the survey. Plant
species, plant size and number of flowers were used to estimate floral
densities. Herbicide treatments had no effect on the floral densities of
either 3-4 year old clearcut or 10-12 year old clearcuts. In July, floral
densities were highest in the older clearcut sites, lowest in the recent
clearcut sites, and intermediate in 10-15 year old plantations and stands
with a closed canopy of relatively mature trees. In August, goldenrod
dominated the floral abundance values and was highest in the recent
clearcut and plantations. Floral abundance was somewhat lower in the older
clearcuts and virtually absent from the mature stands. The abundance of
two groups of wingless Parasitica across all sites throughout the study
was not related to the floral abundance values in July, but was highly
correlated with the floral abundances of August. The authors speculate
that the hosts of these wingless parasites may feed on goldenrod and that
the dispersal of these tiny, early succession species must be wind
dissemination. These observations are in contrast to the only other report
of the effects of forest management on wingless Parasitica in which the
authors found that a wingless parasite associated with old-growth forests
that were negatively impacted in forests that are fragmented by
The biology and control of yellowjacket wasps in National Parks of Hawaii. Foote, David. U. S. Geological Survey, Pacific Island Ecosystems Research Center, P. O. Box 44, Hawaii National Park, HI 96718.
Hawaii and Maine share invasive species of
ants and yellowjacket wasps as a consequence of extensive range expansions
of predatory social hymenoptera during the past century. However, the
ecological context of these invasions differs dramatically because, unlike
Maine, Hawaii contains no indigenous fauna of social wasps or ants. In the
case of yellowjackets, colony dynamics also differs. In Hawaii's warm
climate, wasp colonies can over-winter and grow to sizes that exceed
several hundred thousand cells. Yellowjackets in these island ecosystems
prey on the endemic insect fauna, thereby potentially reducing prey for
insectivorous forest birds and interfering with pollination of native
plants. The western yellowjacket, Vespula pensylvanica, was first
introduced to the island of Kauai in the early 20th century and
spread to all the major Hawaiian Islands in the late 1970s. This rapid
range expansion coincided with the increased use of refrigerated
containers for trans-Pacific shipments of Christmas trees to Hawaii.
Inspections of Christmas tree shipments in the 1980s by the Hawaii State
Department of Agriculture resulted in the interception of numerous queen
yellowjackets. Sanitation procedures developed jointly with Oregon and
Washington, including the shaking of Christmas trees
before shipment, may have helped keep at least three
other species of yellowjackets out of Hawaii. USGS
scientists have recently begun testing new toxicants to control
yellowjacket wasps in Hawaii Volcanoes National Park. The goal of the work
is to suppress seasonal outbreaks of the wasps in the summer and fall. The
research was carried out in collaboration with Landcare Research in New
Zealand where similar wasp control efforts are underway. The objectives of
this work include testing alternative wasp baits, evaluating non-target
insects attracted to baits, and comparing the efficacy of new yellowjacket
toxicants. White chicken meat has consistently proven to be the most
attractive bait for yellowjacket workers in Hawaii. Fipronil has been
demonstrated to be an effective toxicant for destroying wasp colonies when
mixed with chicken bait that is collected by workers to provision the
nest. Research on minimizing non-target impacts of the wasp baiting
program is focusing on reducing the exposure time of the baits. The
long-term effort required to maintain a wasp suppression program in
Hawaii's national parks reemphasizes the need to keep other species of
ants and wasps, such as the European fire ant, from becoming established
The invasion of the European Hammock spider, Linyphia triangularis, in coastal Maine: preliminary findings on behavior and management. Houser, Jeremy. Neuroscience & Behavior Program, Tobin Hall, University of Massachusetts, Amherst, MA 01003-2410.
The European Hammock spider, Linyphia
triangularis Clerck 1757 (Linyphiidae), has recently become
established in parts of coastal Maine. In high-density areas, native
sheet-web spiders, such as Neriene radiata (Walckenaer 1841) and
Pityohyphantes costatus (Hentz 1850), now appear to be scarce.
L. triangularis aggressively invades the webs of both con- and
hetero-specifics in its native range, parasitizing or even taking over
webs. To examine the ability of the introduced population of L.
triangularis to perform these aggressive behaviors on native Maine
sheet-weavers, we conducted reciprocal web introductions between L.
triangularis and the common bowl-and-doily spider Frontinella
communis (Hentz 1850). In general, L. triangularis was more
successful invading the web of F. communis than vice versa. Web
introductions resulted in co-habitation in 44.9% of trials (n = 49) when
L. triangularis was introduced to the web of F.
comuunis; the reciprocal introduction resulted in co-habitation only
20% of the time (n = 35). In addition, we evaluated the potential for
controlling the invader through a one-time removal experiment. L.
triangularis rapidly re-colonized the removal plots, suggesting that
any management efforts based on direct removal are unlikely to be
successful unless the invader is removed repeatedly.
Attraction of the brown spruce longhorn beetle, Tetropium fuscum (Fabr.), and T. castaneum to spruce cortical volatiles. J. Sweeney1, P. de Groot2, L. MacDonald2, S. Smith3, C. Cocquempot4, M. Kenis5, and J. Gutowski6. 1Natural Resources Canada, Canadian Forest Service, PO Box 4000 Fredericton, NB, Canada, E3B 5P7. 2Natural Resources Canada, Canadian Forest Service, 1219 Queen St. East, Sault Ste. Marie, ON, Canada, P6A 5M7. 3Faculty of Forestry, University of Toronto, 33 Willcocks St., Toronto, ON, Canada, M5S 3B3. 4INRA. Laboratoire d'Écologie animale et de Zoologie agricole, 2, place Pierre Viala, 34060 Montpelier Cédex 01, France. 5CABI Bioscience Switzerland Centre, 1, Rue des Grillons, 2800 Delémont, Switzerland. 6 Forest Research Institute, Department of Natural Forests, 17-230 Bialowieza, Poland.
The brown spruce longhorn beetle (BSLB),
Tetropium fuscum (Fabr.), (Coleoptera: Cerambycidae), is a
quarantine pest recently found established near the port of Halifax, Nova
Scotia. In its native Europe the BSLB mainly attacks weakened Norway
spruce but in Nova Scotia it is infesting and killing apparently healthy
red spruce. In 2001, we analyzed cortical volatiles collected in situ
from BSLB-infested red spruce to determine the relative
concentrations of monoterpenes emitted. This information was used to
create a synthetic "spruce blend" which was field tested in trapping
trials in Halifax, NS, in 2001 and in Halifax and Europe in 2002. Spruce
blend-baited traps captured significantly more T. fuscum than
unbaited traps in Halifax in 2001 and 2002, but the difference was not
significant in Poland. The addition of an ethanol lure to spruce
blend-baited traps significantly increased capture of T. fuscum
in Halifax and Poland. In the Poland trials, the combined spruce
blend + ethanol lure was also significantly attractive to T.
castaneum (L.), a close species to the BSLB more common in Europe but
not known to be established in Canada or the US. Ethanol or alpha-pinene,
either alone or combined, were not attractive to either Tetropium
species. The Colossus-dry traps caught the most T. fuscum
but mean catch did not differ significantly among the trap types
tested. Our results indicate that the addition of an ethanol lure
synergizes attraction of the spruce blend to both T. fuscum and
T. castaneum. The combined lure is being used in cross-vane traps
as part of the survey effort for the BSLB in Halifax in 2003.
Impacts of Berberis thunbergii (Japanese barberry) on pollination visitation to the co-flowering native plant, Vaccinium augustifolium (lowbush blueberry). O'Neal, Anthony, Constance Stubbs, and Francis Drummond, Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469, and Howard Ginsberg, University of Rhode Island, Patuxent Wildlife Research Center, Kingston, RI 02881.
Invasive species are considered one of the
most detrimental threats to native plant species diversity. Over 200
non-native plant species have been found in Acadia National Park, 70 of
these are potentially invasive, and 16 are considered of high concern.
Ten-minute observations were made during 2002 on three native-invasive
plant pairs in Acadia National Park to determine whether the presence of
an invasive plant of high concern is impacting the pollination of a
co-flowering native plant. Data from the earliest flowering pair,
Vaccinium angustifolium Ait. (lowbush blueberry) and Berberis
thunbergii DC. (Japanese barberry) will be discussed. While all
insect visitors to flowers can be important, one taxon, the bees
(Apoidea), is of special significance. Visitation rates, flower foraging
times, and pollinator community structure are only a few of the important
factors to consider when examining the competition between two
co-flowering plants, such as a native versus an invasive, for pollinators.
In 2002, Apoidea visitation rates to V. angustifolium were
significantly reduced in the presence of B. thunbergii , 2.38
+ 0.45 visits per 10 minutes compared to 1.09 + 0.36 in
control plots, (in all control plots, B. thunbergii was absent
and at least 1.0 km away. Pollinator community structure significantly
differed between the two plant groups and between treatments (control
versus experimental plots). The most common bee visitors were species from
the genera Andrena, Nomada, and Bombus. Flower
foraging time of Andrena spp. on V. angustifolium was
not significantly different between experimental (B. thunbergii
present) and control plots. Floral rewards for both the native and
invasive plants were compared to estimate floral attractiveness to
pollinators. Pollen availability, nectar volume, and sugar concentration
were measured. B. thunbergii averaged 33.6 + 4.79 pollen
grains, 0.46 + 0.09 ul of nectar with a sugar concentration of
18.16 + 2.55%, while V. angustifolium produced 241.64
+ 85.05 grains, 0.31 + 0.07 ul, and 22.81 + 2.71%
sugar. Data from 2003 is currently being gathered, including manipulative
experiments where B. thunbergii is presented in control
Seasonal foraging activity of Myrmica rubra in Mount Desert Island in Maine. Groden, Eleanor1, Francis Drummond1, Jeff Garnas1, Shicai Yan1, and Rick Mack2. 1Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469 and 2MES, Bar Harbor, ME.
Myrmica rubra was first reported in the United States by Wheeler in 1908. Until 2001, there were official records of M. rubra in four locations within Maine, however, anecdotal reports indicated that this invasive species was more widely distributed. Our surveys conducted in 2001 and 2002 found pestiferous populations of this ant in 18 different communities in 8 counties within the state. These sites extend the length of the coast with populations identified from Kittery to Eastport. To assess the impact of populations of M. rubra and the efficacy of control measures for this pest, we have been developing a relative method for sampling M. rubra density.
Foragers of this sugar-loving ant discover and quickly recruit to vials baited with small pieces of surgical gauze dipped in 30-50% sucrose solution. The present studies were designed to assess how foraging activity and attraction to these baited traps varied at different times of the day, over the season, and in response to environmental conditions. Ten to 20 baited vials were deployed at each of three M. rubra infested sites for two hour intervals, every two hours over a 24 h period on two dates in 2001 and five dates from early June through September in 2002. After each interval, the number of M. rubra foragers within the vial were counted and released, and at the beginning and end of each interval, air and soil surface temperatures, relative humidity, wind speed, precipitation, and cloud cover were recorded.
Myrmica rubra was found to forage around the clock from early June through September on Mount Desert Island, Maine. Foraging did vary significantly with date and time of the day, but there was also a significant interaction between date and time. There was a general trend of decreased foraging with time of day from 0 to 24 h. Stepwise regression analysis supported this trend and revealed that foraging also was significantly correlated with increased cloud cover and soil surface temperature, and decreased precipatation. However, evaluation of foraging activity throughout the fall months (September through early November), did reveal a significant sigmoidal relationship between temperature and foraging. Foraging activity increased with temperature from about 6C to 13-14C. Above these temperatures foraging did not appear to increase in response to air temperature. This is consistent with activity observed over the summer months, when no relationship with air temperature was found, but air temperatures did not fall below 13C.
Patterns of artificial nest site colonization and colony movement by the invasive European fire ant (Myrmica rubra) in Acadia National Park. Garnas, Jeff, Eleanor Groden, and Francis Drummond. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469.
In an attempt to understand seasonal patterns
of colonization, colony movement and local spread in the invasive European
fire ant (Myrmica rubra), artificial nesting substrates were set
out in areas of infestation in Acadia National Park in the Spring of 2002
and monitored biweekly throughout the summer and early fall. Myrmica
rubra colonized 45% of the artificial nest sites at least once during
the season, and showed little preference between substrate types. Many of
the colonized substrates were repeatedly vacated and recolonized,
suggesting that colony movement is high, or that M. rubra's large
polydomous colonies are able to relocate nests in response to shifting
optimal conditions for brood production on a short temporal scale.
Artificial nest slates at a control (uninvaded) site resulted in an
identical colonization rate (45%) by native species. These data suggest
the potential for competition for nest sites between M. rubra and
native ants and support the observed pattern of displacement of native ant
fauna by the invasive ant. The relatively low rate of occupancy for both
natives and M. rubra also suggests that neither population is
limited by the availability of suitable nest sites. Early-season 2003 data
will be presented, along with preliminary conclusions concerning M.
rubra's overwintering habits in Maine.
Evaluation of local entomopathogenic fungi for potential biocontrol of the European fire ant, Myrmica rubra L. Yan, Shicai, Eleanor Groden, and Francis Drummond. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469.
The long term control strategy for the European fire ant, Myrmic rubra, should rely on bio-control agents. For soil inhabiting, pestiferous insects such as ants, entomopathogenic fungi may have several advantages. Soil provides the fungus with protection from harmful ultraviolet light and favorable humidity for infection. We collected fresh cadavers from middens associated with M. rubra nests on Mount Desert Island in Maine. These cadavers were surface-sterilized and monitored for signs of fungal infection. Five isolates of Beauveria bassiana and two isolates of Metarhizium anisopliae were recovered from cadavers. Assaying all of these isolates back against M. rubra workers confirmed their pathogenicity. The relative virulence of these isolates against M. rubra is being quantified in the laboratory and compared to a commercial isolate (strain GHA from Emerald Biologicals). Visual comparison of results from 2 replications of an assay comparing the B. bassiana and M. anisopliae isolates from one site with the commercial strain indicate that all isolates caused greater mortality than the control after 10 Days at all concentrations above 104 conidia per ml in the first trial, and 106 conidia per ml in the second trial. In both trials mortality increased with log concentration of conidia for all isolates. There does not appear at this point to be any consistent differences between the isolates.
It is also reported by others that low
concentration of boric acid can effectively control pestiferous ants. We
exposed M. rubra foragers to one of a range of boric acid
concentrations between 0 and 5% in a 10% sucrose bait. Mortality did
increase with boric acid concentration with LT50 equaling about
12 days at 1% boric acid (the concentration recommended for other
pestiferous ants). Effects on consumption were more variable. Future work
will investigate potential synergism between boric acid and fungal
What can we learn from Pogonomyrmex harvester ants, the sister genus of Myrmica, about the venoms, stings, and medical importance of Myrmica rubra. Schmidt, Justin O. Southwestern Biological Institute, 1961 W. Brichta Dr., Tucson, AZ 85745.
Harvester ants of the genus
Pogonomyrmex are widely distributed in Southeastern US, the
southern U. S. prairies, and most of North America west of the Rocky
mountains. The approximately 25 species north of Mexico are major
granivores in many ecosystems with about 8 species being widely familiar
and recognizable by the general public. They are familiar because they are
often large (8 mm), construct large mounds, are numerous, AND they sting.
Their sting is not forgettable by anyone who has had the pleasure of
experiencing it. A sting by a harvester ant typically hurts for 4-8 hours
and produces a deep pain that feels like the "tearing of muscles or
tendons", and comes in waves. The venom produces three other
characteristic, nearly unique responses - localized sweating at the sting
site, erection of the hairs around the sting site, and an unaesthetic pain
or tenderness in axillary or groin lymph nodes. These symptoms are nearly
unique because Myrmica rubra stings appear to produce mini
versions of the same reactions. This suggests a close toxinological
relationship that mirrors the phylogenetic relationship of the two genera.
Pogonomyrmex venom is the most lethal known arthropod venom, with
an LD50 in mice as great as 190 ìg/kg. The lethality of M.
rubra venom is unknown, but likely is also highly toxic. On rare
occasions, Pogonomyrmex stings can cause allergic hypersensitive
"anaphylactic" reactions in which the victim experiences large systemic
skin swellings or rashes, difficulty in breathing, or faintness caused by
decreased blood pressure. These reactions are rare largely because
allergic reactions typically require one or more prior sensitizing stings
before the reaction is elicited. In the case of Pogonomyrmex
stings, individuals remember the experience and tend to go the great
effort not to be stung again. Moreover, Pogonomyrmex ants usually
are not particularly aggressive and do not enter human dwellings.
Myrmica may present a different medical situation for many
reasons: 1) the ants are smaller, less conspicuous, and not as easily
avoided; 2) they more frequently nest in and around human habitations; 3)
their nests are not nearly as obvious as most Pogonomyrmex nests;
4) their population densities may become more extreme; and 5) their stings
hurt much less than Pogonomyrmex stings, and are less likely to
induce extreme human avoidance reactions. These factors all indicate that
repetitive stinging events by Myrmica will be more common than by
Pogonomyrmex. No specific diagnostic medical skin tests or
immunotherapy for Myrmica currently exist in the US, but
immunological cross-reactivity likely exists between the venoms of
Myrmica and Pogonomyrmex: this will lend hope for the
development of future tests and treatments.
Biodiversity and biogeography of ants in New England bogs and surrounding forests. Ellison, Aaron M. Harvard University, Harvard Forest, P.O. Box 68, Petersham, MA 01366.
I describe species diversity and geographic
patterns of ants in ombrotrophic bogs and the forests that surround them
in Connecticut, Massachusetts, and Vermont. In both bogs and forests,
species diversity generally increases from north to south, but is lower on
the islands of Martha's Vineyard and Cape Cod than on the mainland of
Massachusetts. Contrary to expectation, the ant fauna of bogs is distinct
from that of surrounding forests. The dominant species of ant in New
England bogs is Myrmica lobifrons, a bog specialist that was
previously unrecorded from New England. In addition, several southern
species are near or at their northern extent in southern Massachusetts and Cape Cod, and
several boreal species are near or at their southern extent in northern
Vermont. These data provide a good baseline with which to evaluate
long-term effects of climate change on a discrete insect fauna.
The effects of clearcut age and herbicide application in Maine on the ant community. Lough, Kerry, Francis Drummond, Steve Woods, and Connie Stubbs. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469.
The short and long-term effects of herbicide
application on the diversity and abundance of ants in Maine clearcuts was
assessed in a two-year study. Herbicides, such as glyphosate, are applied
to release coniferous trees from suppression by competition with deciduous
vegetation after a forest is harvested. Previous research indicates
glyphosate has limited immediate and long-term effects on non-target
fauna, though specific species can be affected. Limited research on the
impacts of herbicides on non-target insects indicates some initial
decrease in insect populations. Beneficial insects, such as pollinators
and predators, positively influence the forest ecosystem, but little
research has examined the effects of herbicide application on those
insects. Ants are predators of a variety of insects, including those
considered pests. The presence of ants in the forest may influence pest
population abundance and thus indirectly affect the abundance and
diversity of vegetation. Therefore, land managers need to understand the
effects of herbicide application on ants to determine the impacts of their
land management strategies.
Eighteen study sites in western Maine were utilized, included young (3-5 years since harvest) herbicide treated, young non-treated, old (10-15 years since harvest) herbicide treated, old non-treated, plantations and non-harvested sites. In 2000 and 2001, pitfall traps were used to assess the diversity and abundance of ants.
A total of 4123 ants were collected in both
years. Six genera and 13 species were found. In both years, ant captures
in old sites were significantly higher than in young sites indicating that
age since harvest influences ant abundance in a clearcut forest landscape.
In 2000, a higher abundance of total ants were found in young herbicide
treated than young untreated sites and in old treated than in untreated
clearcuts, but there was no difference in the ant diversity among
herbicide treated sites. Similarly in 2001, there were more total ants in
young herbicide than non-herbicide and in old herbicide than in
non-herbicide, but ant diversity was higher in old herbicide sites than in
young herbicide sites. The abundance of ants across all species, including
Formica spp., Myrmica spp., and Camponotus
spp., tended to be lower in the young non-herbicide sites and higher in
old herbicide sites with variations on this theme that were specific to
individual species or groups of species.
Effect of Myrmica rubra invasion on native invertebrate communities. Drummond, Francis and Jeff Garnas. Department of Biological Sciences, 5722 Deering Hall, University of Maine, Orono, ME 04469.
The invasive ant, Myrmica rubra L.,
has become a noxious pest species in many parts of its introduced range in
Maine. Densities of M. rubra nests can be as high as 4 per
m2 with more than 5200 workers and 39 queens per nest. Do these
high densities of M. rubra affect invertebrate communities? In
1997 (Oulette and Manski unpublished data) and 2001 (Groden and Drummond
unpublished data) sucrose baits were deployed in both M. rubra
infested and non-infested areas for ca. two hours. Ants were collected at
the baits and either identified to species or sorted as morphospecies.
Analysis of these data showed that native ant species that recruit to
sugar baits occur in decreasing richness as M. rubra density
increases within the landscape. In 2002, pitfall trapping in M. rubra
infested and non-infested areas showed a significant decrease in
native ant species richness due to M. rubra establishment. The
non-ant invertebrate community was also shown to be affected by the
presence of M. rubra. Our pitfall trapping study in 2002 in three
different locations within Acadia National Park showed that the
invertebrate community in M. rubra infested habitats had on average only
69% of the richness found in non-infested areas (p=0.058), 53.7%
of the diversity found in non-infested areas (p=0.009), but 194%
of the total invertebrate abundance found in non-infested areas
(p=0.02). The only significant difference in abundance of the
major taxa trapped in these sites was that of sowbugs (Isopoda). Sowbugs
were significantly more abundant (813% more) in M. rubra infested
sites than non-infested sites. However, even after taking out the sowbug
trap captures, diversity of invertebrates was still higher in non-infested
areas compared to M. rubra infested areas. We often encounter
sowbugs within M. rubra nests in the field. The possibility of
myrmecophily is discussed. Other topics introduced are the effects of
M. rubra on pollination, seed dispersal, and small mammal
Territory defense by the invasive fire ant Solenopsis invicta. Adams, Eldridge S. Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269-3043.
In aggressive ants, defense of foraging
territories is a key mechanism of population regulation. We studied a
Florida population of the fire ant Solenopsis invicta, an
invasive species native to South America. Our previous work has shown that
territory sizes and colony growth rates are strongly affected by competition among neighbors. In this study, I
examined the mechanisms of territory maintenance to determine how
neighboring colonies establish or shift boundaries. Large fights occur
naturally when two colonies find the same food item near a territory
boundary. When such encounters were stimulated experimentally, group
responses included both recruitment of nestmates to the site of the battle
and tendencies to flee from areas of strong opposition. The interplay
between these conflicting tendencies caused large fluctuations in arrival
rate, until the losing colony withdrew from the contested area. Major
workers were more likely than minors to remain in the region of the fight.
Despite the ease with which fights can be stimulated, rates of fighting at
unmanipulated boundaries were very low, suggesting that the total mortality is negligible at the colony level.
Boundaries appear to be maintained by simple mechanisms including
exploitation (colonies remove food closer to their own entrances, so that
intruders find no reward) and priority effects (the first colony to
recruit to a food item has a competitive
advantage), rather than by large-scale battles.
Molecular systematics of the subfamily Ponerinae: a phylogenetic study of tribe-level relationships. Ouellette, Gary D.1, 2, Derek J. Girman1, and Brian P. Fisher2, 1Department of Biology, Sonoma State University, Rohnert Park, CA 94928; 2Department of Entomology, California Academy of Sciences, San Francisco, CA.
Ants are considered one of the most
ecologically and numerically dominant groups of organisms found in almost
every terrestrial habitat. However, historical relationships among the
family Formicidae are currently poorly understood impeding our
understanding of ant evolution. Historically, the subfamily
Ponerinae is considered relatively primitive and may have retained many
plesiomorphic conditions from the ancestral formicid. Traditional
phylogenetic studies of Ponerinae have focused on morphological characters
to determine relationships. Here we present preliminary results generated
from DNA sequence data to investigate relationships among the subfamily
Ponerinae with an emphasis on higher-level phylogeny. The objective of the
study is to determine tribe-level relationships. 1230 base pairs from the
28S rRNA gene, Domain 1- Domain 3, were sequenced from 51 taxa
representing 6 ponerine tribes. Preliminary data suggests major groups as
defined by morphological data. However, Ectatommini is found separated
from the remaining ponerines rendering the subfamily polyphyletic. In
addition, the genus Probolomyrmex is nested within the tribe Proceratiini
as suggested in early literature. The information from this study will
have broad application to future work in systematics and may present new
understanding on ant evolution shedding light on the evolution of
important traits within ants.
The Nearctic species of the ant genus Myrmica: actual state and taxonomic revision outlines. Dr André Francoeur, Université du Québec à Chicoutimi, Centre de données sur la biodiversité du Québec, 637-108 boulevard Talbot, Chicoutimi, Québec G7H 6A4.
The last revision of the ant genus
Myrmica for the Nearctic region (except the Mexican part) dates
back in 1950 with the book of Creighton The Ants of North America.
Creighton identified 10 species and 8 subspecies in its key, the only
general one available presently. Since then, some new species were
described and some old names were resurrected from synonymy. Bolton (1995)
recognized 24 taxa in his world ant catalog. Historically, the ant
taxonomy sank into a dead end with the usage of a four-level nomenclature
based on the Linnean species concept. This context must be known for a
reliable use of the literature. A revision based on modern standards was
undertaken to identify the natural species. The examination of all the
types of all past taxa revealed that type series of older names may
include more than one species, and many actual species concepts in the
literature are not in agreement with types or constitute artificial taxa.
The revision, almost completed, identifies 15 species groups and 41
species, of which 14 are new (mostly from the West of the continent) and
four are resurrected old names. The Northeastern ant fauna includes 18
native and two introduced species. A key for this fauna is
Entomological Society 63rd Annual Business
Total Members Present: 12
(Total AES Membership: 29; 20
regular, 9 students; 9 Canadian, 20 American)
A quorum was present.
The Treasurer's Report was approved as written.
Minutes of the 2002 AES Annual Business Meeting were
approved as written.
The responsibilities of the Society were passed on to New Brunswick members. Jon Sweeny agreed to be the acting President and will canvas other interested members (and past members) for officers.
The 64th annual meeting will be held in Prince Edward Island in conjunction with the Entomological Society of Canada in October 2004. A brief discussion followed on how Maine created such dynamic meetings in 2002 and 2003. These meetings had two features that contributed to their success. One was a hands on workshop with experts that attracted participants from across the continent. The second was a joint meeting with the Maine Entomological Society combined with a collecting trip that lured nonprofessionals to the meeting. Their enthusiasm and expertise in various areas of entomology not always covered by paid entomologists added greatly to the meetings and they gained by participating in scientific forum.
Notes on the 2003 AES Meeting
Sixty-seven people attended the Paper Presentations on Monday and Tuesday morning with another 22 of the general public coming in to hear the keynote speaker, Graham Elmes of the Centre for Ecology and Hydrology, Dorset, UK. Attendees were from; Arizona, California, Connecticut Maine, Massachusetts, New Brunswick, New Hampshire, New York, Pennsylvania, Rhode Island and Vermont.
Twenty-seven papers, including seven student submissions, were presented.
Twenty-six people participated in the "Ant Blitz" in Acadia National Park organized by Ellie Groden and Frank Drummond. There were six teams consisting of an ant expert, a person familiar with the area to be searched and two or three additional team members.
Twenty people went collecting at Donnell Pond Public Reserve in T9 and T10 SD, on Sunday.
Twenty-six people attended the Ant Workshop Tuesday afternoon for hands on practice at identifying ants either at the family or species level.
The President's Award for the best student
presentation was awarded to John Martel, University of Maine for his
presentation: Synthetic host volatiles increase
efficacy of trap cropping for management of Colorado potato beetle, Leptinotarsa decemlineata (Say).
(Acadian Entomological Society Homepage)