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HUNTSMAN MARINE SCIENCE CENTRE, ST. ANDREW'S NB (UNB) 2000 COMMON EIDER (Somateria
mollissima) DUCKLING PREDATION BY HERRING GULLS (Larus
argentatus) DURING COLONY DEPARTURE Attempts to quantify brood departure activity and predation during the nest-to-sea portion of the eider breeding season are often hindered by vegetation, dark periods and human disturbance. The present study, initiated in 1999, takes place at a remote eider colony in the eastern arctic, where the Canadian Wildlife Service has established blinds equipped with tunnels for discrete observation of breeding birds. Brood departures from the colony may be partially constrained by presence of predators, tide, wind and luminosity. Herring gulls are known predators of eider ducklings in the Eastern Arctic. High winds allow gulls to hover, providing them with increased ability to attack. If wind provides an advantage to herring gulls by allowing them to hover, then gull air patrol activity and duckling predation should be greater during windy periods. Broods travel distances sometimes exceeding 200m, often over boulders and/or through vegetation, in order to reach the sea. Low light makes visual contact between hens and ducklings difficult, and foraging ability on the water may be impeded, especially for young, inexperienced ducklings. Departure activity should vary diurnally, slowing when darkness or surf stalls departing broods. A trade-off may exist between their ability to maintain visual contact, forage efficiently, tides, favourable weather conditions for departure, and risk of predation by gulls. AN EXAMINATION OF THE EFFECTS OF
ASPATIAL AND SPATIAL HABITAT FACTORS ON THE REPRODUCTIVE SUCCESS OF
FOREST BIRDS In an effort to conserve biodiversity on Crown land in New Brunswick, the Department of Natural Resources has adopted an 'indicator species approach'. A range of avian indicator species has been selected to represent other species that are dependent upon critical habitat types. The major objective of this research project is to quantify relationships between forest structure and the reproductive success of mature forest-dependent song birds. At this preliminary stage of research, two major questions have been developed: (1) What are the stand-level habitat requirements of mature forest birds?, (2) Does (a) habitat patch size, or (b) landscape context influence habitat quality for mature forest birds? If landscape effects are detected, hypotheses explaining the mechanisms for these effects will be tested. Two 25km2 study areas were established in the Greater Fundy Ecosystem in southeastern New Brunswick. Survey points (n=217) are located in a range of patch sizes (1 - 150 ha) of hardwood and mixedwood stand types in different successional stages. Point counts and the mobbing playback method were used to determine the density and reproductive success of forest song birds in different treatment types. As an additional potential measure of habitat quality, territorial males of four focal species were aged (Blackburnian Warbler [Dendroica fusca], Black-throated Green Warbler [Dendroica virens], Black-throated Blue Warbler [Dendroica caerulescens], Ovenbird [Seiurus aurocapillus]). In later years, intensive nest monitoring plots will be established to provide a more detailed assessment of reproductive success, and to calibrate the mobbing method. FACTORS AFFECTING COMMON EIDER BROOD
HABITAT USE ON THE NEW BRUNSWICK BAY OF FUNDY MAINLAND Common Eider broods (Somateria mollissima) were observed at 12 sites along the Bay of Fundy mainland to determine if factors such as proximity to Great Black-Backed Gulls (Larus marinus), Herring Gulls (Larus Argentatus), rockweed harvesting and other disturbances were involved in the use of brood rearing areas. The sites comprised 4 Special Rockweed Management Areas, which have restricted harvesting, 4 Study Sites, which are completely protected from harvesting and 4 rockweed harvested sectors. The number, age-class and behaviour of ducklings were recorded as well as the number and behaviour of attending female(s). Observations were made for a 6 hour period for 4 days with 1 day off between rotations from June 15th to August 13th, 2000. Rockweed density measurements were taken to assess the availability of habitat necessary for feeding. VARIABILITY IN TIMING, INTERCOLONY
MOVEMENT, AND SUB-ADULT SURVIVAL OF ATLANTIC PUFFINS (Fratercula
arctica) IN THE GULF OF MAINE Atlantic Puffins nest on five islands in the Gulf of Maine (GOM). At each site, adults and chicks have been color-banded. Over 6000 Puffins have been banded with over 30,000 recorded sightings. In other parts of the Puffin's range, young birds visit colonies close to their natal sites before choosing a colony to breed. In addition, as sub-adults mature to breeding age (5-6 years), variability has been observed in timing of return to colonies and in intercolony movement. We plan to analyze the GOM data set to identify trends in sub-adult movement between colonies and sub-adult survival rates. Questions we address include: What variability is observed in age of first return? Does the rate of intercolony movement vary as a Puffin matures and eventually initiates breeding? What is the sub-adult survival rate of Atlantic Puffins? Do we find variability in these parameters between islands and years? What characteristics of colonies are associated with this variation? SPATIAL DISTRIBUTION AND
COLONISATION OF PITCHER PLANT INHABITING INSECTS Commercial timber harvesting occurs in the Main River area of western Newfoundland. The effects of the cutting on animal movement are being studied for different species of birds and invertebrates in the area. I am studying the movements of two species of insects whose larvae exclusively inhabit pitcher plant leaves (Sarracenia purpurea), Wyeomyia smithii (mosquito) and Metriocnemus knabi (midge). My objective is to examine the spatial distribution of the plants and insects, the insects' colonization abilities, and whether either was affected by the surrounding habitat. I removed all leaves (and consequently all mosquitoes and midges) from 30 m diameter circles in bogs surrounded by: forest, clear-cut and unmerchantable scrub. I will present the methods used, as well as preliminary results of the spatial distributions. NO PLEASE, AFTER YOU: IS THERE A
SEX-BIAS IN TRAPPING ARCTIC TERNS AT THE NEST? On Machias Seal Island, in the Bay of Fundy, we captured 48 adult Arctic Terns (Sterna paradisaea) at nest sites in 1998. We did not try to capture both members of a pair. Traps were re-set on new nests once one tern was captured. We recorded morphological measurements to determine if there were any size differences between the sexes and collected feather samples for an analysis of DNA to determine the sex of individuals. These birds were sexed using PCR and 1 positive sexing primer (Sabo et al. 1994. Auk 111:1023-1027). A strong bias in the results (35 males, 13 females) indicated a sex-bias in which member of a pair entered a trap first. In 1999 we captured 53 pairs of Arctic Terns (N=106) and recorded the timing of each trapping event and morphological measurements. Birds were sexed using PCR and 2 positive sexing primers (Fridolfsson and Ellegren. 1999. Journal of Avian Biology 30:116-121). The timing of our trapping in 1999 was similar to the trapping time in 1998. We found no evidence of a sex bias in trapping terns at the nest in 1999. We will discuss the differences in sexing techniques and the use of a discriminant function based on morphological measurements to sex Arctic Terns in the field. MONITORING VERSUS RESEARCH; LESSONS
FROM MACHIAS SEAL ISLAND 2000 On Machias Seal Island the long-term ACWERN program includes routine monitoring of ecological and life-history parameters such as numbers, productivity, growth rates, survival, and diet. Interpreting year-to-year, or within-year, changes in these parameters, requires focused research to determine cause-effect relationships. In summer 2000 chicks of Razorbills, and Arctic and Common Terns, fledged at normal rates with apparently normal growth; but Puffins fledged late and well below normal weight. All four species feed mainly on herring. Results from previous experimental studies of effects of food shortages on puffin chick growth allow us to interpret what happened to the seabird food supply. USING RADIO TELEMETRY TO CENSUS
BREEDING RAZORBILLS IN A HETEROGENOUS HABITAT We attached radio transmitters to twenty-four adult, breeding razorbills (Alca torda). We also counted all the nest sites we could find in all available and/or occupied breeding habitat between peak lay and peak hatch. We tracked each marked bird to its nesting site, and scored it according to whether or not it would have been recorded in the census. We then calculated a correction for the number of burrows that would not have been found during the census. We applied the correction to the sections of razorbill habitat where we were sure that we could not count all the nests based on the structure of the habitat (i.e., habitat dominated by large boulders). Similar methods have been employed successfully with other groups of birds (e.g. waterfowl) and we suggest it can be used to establish appropriate 'k'-factors for calibrating counts of cavity-nesting seabirds in heterogeneous habitats. IS DENSITY A MISLEADING INDICATOR OF
HABITAT QUALITY? THE RELATIONSHIP BETWEEN FOREST SONGBIRD ABUNDANCE AND
REPRODUCTIVE SUCCESS THE EFFECT OF LANDSCAPE STRUCTURE ON
PEATLAND DRAGONFLIES AND DAMSELFLIES (INSECTA: ODONATA) We examined the effects of landscape structure on odonates living in peatland habitat. Using a nested spatial design, two separate comparisons of landscape composition were made. In one comparison, the amount of peatland was varied while surrounding habitat was kept consistent. In the other comparison, the amount of peatland was held constant while surrounding habitat differed. Larval and emerging adult populations were sampled and habitat characteristics were measured at discrete pools within each study area. Analyses indicate the amount of peatland and the type of surrounding habitat had effects on both larval populations and emergence of adults, but species responded differently. The most abundant dragonfly, Leucorrhinia hudsonica, was found with a frequency lower than expected in landscapes surrounded by forest, but was also found less than expected in landscapes with much peatland habitat. Small Enallagma damselflies were found less than expected in landscapes with little peatland, and were found more than expected in scrub landscapes, but other odonates showed opposite patterns. Despite the value of using odonates as research subjects in the examination of ecological patterns, interpretation of our conflicting results would be difficult without a knowledge of the natural history of these species. A COMPARISON OF CONDITION AND DIET
OF MIGRATORY COMMON EIDERS (Somateria mollissima borealis)
AND NON-MIGRATORY COMMON EIDERS (S. m. sedentaria)
OF THE EASTERN CANADIAN ARCTIC There are two races of Common Eider (Somateria mollissima) breeding in the eastern Canadian Arctic, S. m. borealis and S. m. sedentaria. One population of S. m. borealis breeds on Southampton Island, Nunavut and migrates through Hudson Strait to their over-wintering grounds in Greenland. S. m. sedentaria, however, is a year-round resident of the Belcher Islands, Nunavut. Preliminary observations suggest that eiders wintering in west Greenland are in poorer condition. This is despite that they are wintering in apparently temperate conditions, when compared to sedentaria eiders over-wintering in Hudson Bay. In this study, I will compare the condition of both races at different intervals throughout the year. I also wish to investigate seasonal changes of diet for both groups. By doing this, I hope to gain some understanding of why these two races have adapted different over-wintering strategies. Collections for S. m. borealis will occur twice during out-migration, once at over-wintering grounds and twice during return migration. Simultaneous collections will be carried out for S. m. sedentaria. The ducks will be shipped to New Brunswick for dissection. Condition data will be taken from birds captured on the breeding grounds. MORE ISN'T ALWAYS BETTER: THE
IMPORTANCE OF HABITAT STRUCTURE CHANGES WITHIN A NESTED HIERARCHY OF
SPATIAL SCALES FOR THREE SPECIES OF INSECTS The larvae of three species of inquiline insects, Wyeomyia smithii, Metriocnemus knabi, and Fletcherimyia fletcheri obligately develop within the leaves of the pitcher plant, Sarracenia pupurea. This strict habitat requirement is the smallest component of a naturally nested hierarchy of structural spatial scales including: leaves within plants within cluster (of plants) within bogs. This study examines the relative importance of amount of habitat and configuration of habitat in a hierarchical analysis of the distribution of three insect species with the same discrete habitat requirement. The results illustrate that there are changes both in the direction and importance of the relationship between organisms and habitat structure (amount and configuration of habitat) across multiple spatial scales nested within the same system. In general, amount of habitat influences density at relatively finer, and configuration at broader spatial scales, though species respond at slightly different absolute scales corresponding to evolutionarily divergent attributes such as body size and/or movement potential. PARTNERS IN FLIGHT Partners in Flight--Canada works on landbird conservation issues in partnerships with government, universities, industry, conservation groups, and individuals to identify species and habitats of concern, educational and research needs, and programs or policies to implement needed changes. Each province or region has responsibilities for specific landbirds and issues particular to the region. In Atlantic Canada several conservation needs already have been identified, and a regional working group soon will be formed after an initial workshop brings the interested parties together. Specific concerns of this group will focus on birds with trends that appear to be declining, and birds for which there is little information or are being missed by present monitoring methods. This talk will elaborate on how the PIF approach gets results. A NEW METHOD FOR CALCULATING THE
ABUNDANCE OF ARTHROPODS AVAILABLE TO FOLIAGE GLEANING INSECTIVOROUS
SONGBIRDS AND THE ROLE OF TREE SPECIES LEAF AND BRANCH MORPHOLOGY Foraging Black-throated Blue Warblers (Dendroica caerulescens) and Black-throated Green Warblers (Dendroica virens) were highly selective in their use of the American Beech (Fagus grandifolia) as compared with the Yellow birch (Betula alleghaniensis). A traditional calculation of arthropod density based on leaf area indicated a significantly higher density of most arthropods in Yellow Birch. A calculation of arthropod density based on the arthropods available along a length of branch, however, indicates nearly equivalent arthropod densities. This is because American Beech has a higher volume of foliage along a given length of branch. This seems to be the more relevant measure of arthropods available to a leaf gleaning bird. Selective use of the American Beech remains and is best explained by the existence of an optimal relationship between the foraging strategies of the birds and the leaf and branch morphology of the American Beech. EFFECTS OF LANDSCAPE CHANGE AND
FOREST REGENERATION ON ABUNDANCE OF ODONATA IN WESTERN NEWFOUNDLAND Movements and distributions of many organisms are changed when landscapes are altered by human use. But often, the impact on species in adjacent habitats is less understood. The balsam fir/ peat land ecosystem near the Main River, Newfoundland has been extensively logged; we question how this activity has affected populations of peatland dragonflies. In particular, we are interested in whether spatial structure of populations is altered and 2) whether these changes are caused by finer-scale characteristics of bogs or 3) changes to landscape connectivity. To determine how species abundance relates to the type of habitat in which bogs are imbedded and how this changes as forest regenerates, sampling was done in 7 types of bogs with 4 replicates of each. Exuviae (shed exoskeletons) of all odonate species were collected at water pools in bogs surrounded by: mature forest, scrub, and clear-cuts from 1991, 1994, 1995, 1997 and 1998. The structure of pools - water depth, pH, bank slope, bottom type, and emergent, submergent and surrounding vegetation - was also measured. This information will allow us to model the effects of landscape change on abundance of many species at pool, bog and landscape scales. SEX DIFFERENCES IN NEST ATTENDANCE
AND DIVING BEHAVIOR OR THICK-BILLED MURRES (URIA LOMVIA)
AT THE GANNETS ISLAND, LABRADOR Emerging evidence points to striking male-female differences in patterns of parental care in monogamous seabirds. We investigated this issue at the Gannet Islands, Labrador during June-August 2000. Twenty-five nesting pairs of Thick-billed murres were observed continuously from egg-laying, through incubation, until chick fledging in order to quantify male-female differences in nest attendance, feeding frequency and prey (species and length size) delivery to chicks. Depth time recorders (19) and temperature loggers (3) were deployed on 22 of these birds to obtain information of diving behavior (number of dives, dive duration, dive depth, and ascend speed and descend speed of dives) during the brooding period. Sex was determined for 8 individuals based on position during copulation, blood samples were collected from the other individuals for genetic sexing from their DNA. Preliminary data confirm that there are strongly different patterns of nest attendance, feeding frequency and foraging behavior between sexes in Thick-billed Murres. Our study addressed questions about parental investment and provides a better understanding of murre foraging behavior that hopefully will aid conservation of this species. PREDICTING HABITAT REQUIREMENTS:
TESTING A GIS BADED HABITAT MODEL FOR FISHERS (MARTES PENNANTI) IN NOVA
SCOTIA Efforts to re-establish fisher (Martes pennanti) over their former range in Nova Scotia provide an opportunity to test the efficacy of predictions of fisher habitat choice made by GIS models. Using statistical models, aggregations of fisher harvest locations collected from 1987-1999 were associated with attributes from the Nova Scotia forestry database. Attributes were selected based on review of pertinent literature and data gathered from radio-marked individuals followed in natal territories. The resulting models were used to select potential areas of preferred and non-preferred habitat in counties currently unoccupied by fishers. Testing of habitat predictions involved translocating individuals to areas selected as preferred/non-preferred and monitoring response via radio-tracking. Animals were located 2-3 times weekly with a subset of individuals followed for 24 hour periods. Daylong tracking will be used to compare movement patterns in natal versus relocation areas and will help correct for variation among individuals. The extent to which the model predicts fisher habitat will be based on individuals': i) movements immediately following release, ii) proximity to release site, iii) time spent in vicinity of release site and iv) movement patterns within release area. We anticipate that the value in examining how fishers respond to landscape-scale structure, as well as our ability to explicitly test a GIS-based habitat model will be useful more broadly in other re-introduction and management programs. THE ATLANTIC CANADA CONSERVATION
DATA CENTRE (AC CDC) The Atlantic Canada Conservation Data Centre (AC CDC) exists to assemble and provide information and expertise on species at risk and natural communities in Atlantic Canada, and to undertake field biological inventories, in support of decision-making, research and education. The AC CDC was incorporated as a non-profit organization in 1999 and publicly launched on October 3, 2000 at Mount Allison University in Sackville, New Brunswick, where the centre is based. The AC CDC fills a need to develop and manage information on rare and endangered species in a standardized format and make it more widely accessible and available using advanced information technology. In doing so the AC CDC follows procedures that are common to all 90 or so CDCs located throughout the Americas, from Alaska and Hawaii, across Canada and the contiguous U.S., and into the Caribbean and Latin and South America. The centre is made possible by the support of nine founding partners and additional support from other partners and funding sources. The centre currently employs eight people including two botanists, four zoologists, a data manager and an administrator. Critical to the centre's success are cooperative agreements with partner organizations, enabling the sharing of information and expertise. In this regard, the AC CDC seeks strong linkages with students and researchers working under the umbrella of ACWERN. SONGBIRD ABUNDANCE AND FECUNDITY IN
RELATION TO FOREST STRUCTURE AND PRODUCTIVITY Commercially valuable timber in central Labrador typically occur in small stands which are imbedded within a matrix of softwood scrub. These stands differ from those of non-commercial value in structural diversity, tree size, nutrients and slope - factors known to affect forest birds. In order to make predictions about large scale logging these stands, I am comparing the habitat quality of these stands with stands of no commercial value. Relative bird abundance was gathered on 225, 10-minute point count stations that were established within five conifer stand types. Stands ranged from non-commercially valuable to highly valuable. A five minute playback of chickadee mobbing calls was used to evaluate bird fecundity. AN EXPERIMENTAL STUDY OF FAUNAL
COMMUNITIES IN SMALL WETLANDS ON PRINCE EDWARD ISLAND I explored anuran and avian use of small, non-managed and managed (i.e. excavated) wetlands on Prince Edward Island. Pairs and broods of green-winged teal and American black ducks were significantly more numerous on managed wetlands than on non-managed wetlands. American black duck brood occurrence was positively correlated with proximity to freshwater rivers and greater cattail cover in managed wetlands. Diversity of wetland obligate bird species was higher on managed wetlands than on non-managed wetlands. Principal components analysis revealed five bird communities. Two of these consisted of non-waterfowl species and were positively associated with vegetative cover. A community consisting of tree swallows, American black ducks, blue-winged teal, and belted kingfishers was more frequent on managed sites than on non-managed sites. Relative abundance of green frogs, northern leopard frogs, and spring peepers was significantly higher on managed wetlands than on non-managed wetlands. Small wetland excavation may be a good conservation and management tool for anurans and birds associated with open water wetlands; however, additional research on reproductive success and population trends is required to determine if management created additive habitat and increased local populations. LARGE-SCALE EFFECTS OF LANDSCAPE
STRUCTURE ON SONGBIRDS IN WESTERN NEWFOUNDLAND We examined the effect of landscape structure on songbirds in Gros Morne National Park, NF in 1999. For each of the 14 most common species, we examined how incidence at 280 points across 14 sites was related to the total amount of forest habitat at a point (to remove bias due to the relative probability of detecting a species simply due to the amount of habitat present in the immediate vicinity of a point) , the local habitat at a point (as defined by the four canonical scores describing the vegetation) and the amount of forest cover in a 2500 m diameter circle around the point (linear + quadratic term). After accounting for variation in incidence due to local habitat type and amount, we found significant large-scale treatment effects for 12 of the 14 species. When viewed graphically, we find three kinds of responses to different levels of forest cover at the large scale. 5 species decreased in relative incidence with decreases in forest cover, 6 species show peak incidences at middle levels of cover and 3 species increased with decreasing amounts of forest cover. The non-linear nature of the effect of the amount of forest cover on species incidence at a large scale, after accounting for the effects of amount of forest cover at a smaller scale, suggests that variables associated with landscape heterogeneity (e.g. predation and movement) have significant effects on forest songbirds in naturally heterogeneous environments. FORAGING ECOLOGY AND OFFSPRING
GROWTH RATES OF GREAT BLACK-BACKED GULLS AT CULL ISLAND, NEWFOUNDLAND
AND THE GANNET ISLANDS, LABRADOR Competition can be based on temporal and/or spatial food source limitations to individuals. Great Black-backed Gulls (Larus marinus) are generalist predators, feeding on intertidal invertebrates; smaller birds and mammals; the food of, and the young of other breeding seabirds and waterfowl; carrion; and human refuse. Both Gull Island and the Gannet Clusters are rich in prey items but Gull Island has nearby sources of human refuse. In addition to nearby dumps Gull Island has a population of breeding Herring Gulls (Larus argentatus) which outnumber the Great Black-backed Gulls approximately thirty-to-one. All Great Black-backed Gulls fed their chicks seabirds (mostly auk eggs) in the Gannet Islands, while on Gull Island, adults fed chicks seabirds (mostly adult puffins, kittiwakes and petrels), and/or garbage. Among adults that fed their chicks seabirds, chick growth rates (up to 22 days of age) were faster on the Gannet Islands than on Gull Island. Further, on Gull Island, chicks fed seabirds tended to grow faster than chicks fed garbage. We suggest competition on Gull Island has forced adults to work harder to get seabirds, or to feed on easily accessible, but less nutritious garbage, resulting in smaller chicks with lower growth rates. ASSESSING HABITAT QUALITY OF CAVITY
NESTERS IN AN INDUSTRIAL LANDSCAPE The primary objective of this study is to assess habitat quality for a guild of cavity-nesting birds in an industrial landscape. Traditional evaluations of wildlife habitat have used species density as a measure of habitat quality. However, habitat quality may be better defined using measures of productivity in addition to density. Determining the productivity of birds by locating and monitoring nests can be prohibitive in terms of time and cost, and is often not conducive to long-term monitoring on a landscape scale. Reproductive indices based on breeding behaviours have been used to estimate relative reproductive success in grassland songbirds, however limited visability in forest habitats make detecting these behaviours more difficult. This talk will investigate the use of chickadee mobbing and barred owl calls to increase the number of detections and visual observations of a cavity-nesting bird guild in the Acadian forest. THE EFFECTS OF WIND ON THE DISPERSAL
OF MUSCA DOMESTICA IN AN AGRICULTURAL LANDSCAPE Wind can play an important role in the dispersal of houseflies, whether by directing flight in a given direction or by bringing odour-based attractors to an emergence site. Our study looks at the effect of wind speed and wind direction on a marked fly release over two time scales in an agricultural landscape. First, we looked at how houseflies are influenced by initial wind conditions at the time of release and second, how important wind effects are to their overall dispersal pattern over the duration of the release. Data were collected using Mass Mark Resight and Recapture experiments over an entire fly season and were analyzed for their potential use as predictors in managing housefly outbreaks. The experiments were conducted in Grand Pré, Nova Scotia and were part of a two-year study of housefly dispersal. Results show that flies do initially fly faster with the wind and initial wind direction and fly's orientation have significant effects on the final dispersal pattern. The project includes extensive cooperation with area farmers, Parks Canada, and the NS Department of Agriculture and Marketing.
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