|
Atlantic
Cooperative Wildlife
Ecology Research
Network
|
| Canadian Wildlife Service | Acadia University | Memorial University of Newfoundland | University of New Brunswick |
| Abstracts | Publications | Students | Research Associates | About Us | Contact Info | News | Listserve |
|
KOUCHIBOUGUAC NATIONAL PARK, NB (CWS) 2005 Reorganization
and research in the Canadian Wildlife Service The Species at Risk Act (SARA) was introduced and deemed to have passed all stages as Bill C-5, in the House of Commons on October 9th, 2002. The purposes of the Species at Risk Act are to prevent wildlife species from becoming extirpated or extinct; to provide for the recovery of wildlife species that are extirpated, endangered or threatened as a result of human activity; and to manage species of special concern in order to prevent them from becoming at risk. Building on principles established under the Accord on-going recovery efforts have been underway in Atlantic Canada since the 1980's. However, with the passing of SARA, these programs have become more prescriptive in their requirements, supporting recovery targets (species or ecosystem) for which there are credible recovery strategies, action plans and/or management plans. Additionally, SARA has created mechanisms designed to support targeted recovery programs and provides funding incentives for conservation and recovery actions.
Preliminary results of a Piping
Plover five year banding study in Eastern Canada - support for
expanding conservation efforts to non-breeding sites? An Eastern Canada Piping Plover research program was conducted from 1998-2003, with additional effort expended on recapture in 2004. During this time, 888 Piping Plovers were banded, including 561 young and 327 adults. Individuals were banded with province-specific colour bands, many bearing alpha codes to permit visual identification. Of the total banded, 175 were recaptured in subsequent years, including 73 young and 102 adults. Preliminary analysis has been initiated exploring survival, dispersal, metapopulation dynamics, wintering ground fidelity and migratory tendencies.There appears to be two discrete groups of Piping Plovers in Eastern Canada - one located in southern Nova Scotia, another located in the southern Gulf of St. Lawrence. There is an indication of limited exchange with the US Atlantic population and the Gulf of St. Lawrence group however the Nova Scotia group appears to be isolated from other populations. Survival rates were calculated for both groups independently. Adult survival rates were approximately 73% for both the southern Gulf of St Lawrence and southern Nova Scotia and are comparable to rates calculated for the US Atlantic population. However, juvenile survival rates were substantially lower with estimates of 24% for the southern Gulf of St. Lawrence and 33% for southern Nova Scotia. The population model also identifies adult survival as the most important factor influencing population trends.Several Eastern Canadian individuals have been positively identified during migration and on the wintering grounds. Migration south from the nesting grounds can occur very early. Several individuals have been observed in migration from early to mid July. High fidelity to wintering areas was reported in several individuals, with plovers remaining in an area during an entire winter and returning to the same site in one or more consecutive years. The preliminary results of our study suggest that there are likely factors acting outside of the nesting grounds that must be considered in order to move towards recovery of the Eastern Canadian population.
The relevance of United Nations
Conventions to conservation efforts in Atlantic Canada Overview [no abstract provided]
Seabirds as indicators: Can we know
if feeding is driven by availability or selection? Seabirds are visible upper-level predators of the oceans and are often used as indicator species. It is assumed that they consume prey that is most available. Therefore what they feed on should reflect what is in the marine environment. We have ten years of chick-feeding data for four species of seabirds which breed on Machias Seal Island, New Brunswick. If seabirds are indicator species, we would expect to see different species of seabird feeding on the types of prey which reflect availability as well as any changes in available prey species over time. Contrarily, if seabird foraging is driven primarily by selection, we would expect birds to feed on different prey on the same day.
Common and Thick-billed Murre chick
diet at the Gannet Islands, Labrador, 1981-2005: does it reflect
large-scale changes in the marine environment? Capelin Mallotus villosus and daubed shannies Lumpenus maculates make up most of the diet of murre chicks at the gannet islands. During 1981 - 1983, Common Murre chicks were fed predominantly capelin, while Thick-billed Murree chicks were fed daubed shannies. During 1996 - 2005, the diet of both murre species' chicks was predominantly daubed shannies, although in a few years Common Murre chicks received capelin. Here I evaluate how changes in chick diet might be related to changing environmental conditions, using our long-term chick diet, murre flight directions, and travel time datasets as well as information concerning changes in abundance and distribution of capelin off southern Labrador.
Comparing Arctic and Common Tern
foraging ground characteristics during three stages of the breeding
cycle Study of the breeding biology of Arctic and Common Terns has, for the most part, been focused on behavior at the nest or colony site, leaving at-sea activities relatively unknown. In an attempt to fill in these data gaps we conducted a radio tracking study to identify foraging habitat characteristics of these closely related species. Water depth and distances from the colony and mainland were compared between Arctic and Common Terns, and between 3 nesting stages: incubation, chick rearing and failed nest. No differences in these characteristics were found between species or between nesting stages.
Black-legged Kittiwakes, the North
Atlantic Oscillation, and Climate Change We monitored breeding success of Black-legged Kittiwakes at Witless Bay, southeast Newfoundland from 1990 onwards. Data were also available from 1969-70 and 1988. Breeding success was variable over these years, ranging from over 1 chick per pair to almost zero. Breeding failure was a particular feature of the early-mid 1990s and was proximately caused by high rates of egg and chick loss due to predation by large gulls, sibling aggression, and (probably) low chick feeding rates. Witless Bay kittiwake populations declined as a result. Kittiwakes in eastern Newfoundland feed their chicks capelin, obtained at the surface when the fish migrates inshore to spawn on beaches. Changes in the availability of capelin to surface feeders such as kittiwakes and large gulls were coincident with kittiwake breeding failure. In early 1990s, spawning capelin were smaller, spawned several weeks later, and were found deeper in the water column. Although both kittiwake egg-laying and capelin spawning were delayed in the 1990s, there was a greater mismatch in the timing of capelin spawning and kittiwake egg-laying such that many kittiwake chicks hatched well before capelin had moved inshore. Ultimately, kittiwake breeding success appears to be related to the state of the North Atlantic Oscillation (NAO). We found a strong, negative relationship between kittiwake breeding success at Witless Bay and the NAO index. During the height of the kittiwake breeding failure the NAO index was positive, with anomalously cold water temperatures off eastern Newfoundland. In years when the index was negative kittiwakes reproduced more successfully. The casual link may be through sea temperatures and effects on capelin, although more complex interactions are also likely. Several major climate models predict that the NAO index will increase over the next 100 years with a standard forcing of 1% CO2 increase per annum. This will result in less favourable conditions for kittiwakes and other important marine species known to be affected by the NAO such as the copepod, Calanus finmarchicus.
Herring gulls depredating eider
ducklings: interaction among environmental conditions, indirect trophic
relationships, and risk From 1999 to 2003, we observed common eider (Somateria mollissima) broods departing nests and making their way to the sea. Specifically, we assessed sources of variation in vulnerability of ducklings to attacks by herring gulls (Larus argentatus) at a site where both species breed. Each year, we monitored the progress of randomly selected broods and examined sources of annual variation, effects of day of year (adjusted to timing of breeding), time of day, wind speed, tide and temperature, on aerial and ground search, and duckling capture rates by gulls. Brood location type, gull attack mode, and eider response to gull attacks were also considered. We hypothesised that if defensive hens posed a significant risk to foraging gulls, then gulls would use tactics that lower risks of injury, balancing benefits of prey capture with costs. Gull aerial searches were more frequent on windy days, when they could hover over broods. Eiders defended aggressively, regularly entering into direct physical contact with gulls, occasionally resulting in vigorous struggles. Duckling capture rates at this site were low and highly variable between years, despite high encounter rates with gulls. Specifically, years 2000 and 2001 were characterized with low search and duckling capture rates. These years coincided with a peak in collared lemming (Dicrostonyx groenlandicus) abundance at East Bay. Our findings stress the importance of assessing costs, returns and risks for predators fully, before making assumptions on levels of prey exploitation based on the nature of species involved and their abundance.
Patterns of mercury burden and
stable isotopic ratios of the nesting seabirds of Machias Seal Island Mercury is a pervasive environmental contaminant, the source of which is often anthropogenic. Since mercury bioaccumulates, the highest levels are often found in seabirds, which occupy high trophic positions in marine food webs. Levels have also been increasing in the eggs of some Atlantic seabirds steadily since the 1970's, while others remain unassessed. Using stable-nitrogen and stable-carbon ratios, we will attempt to locate the source of mercury burden spatially and temporally using the non-destructive sampling of various seabird tissues. By examining a wide array of species with varying feeding habits, we will essentially sample the marine food web through the seabirds.
Phylogeography of Ivory Gulls (Pagophila
eburnea) and Ross's Gulls (Rhodostethia rosea) We are investigating the circumpolar population structure of Ivory Gulls and Ross's Gulls using mitochondrial DNA. Are Ivory Gull populations composed of discrete groups or is there gene flow between colonies? Furthermore, most Ivory Gulls winter in Canadian territory, but which colonies are they from? A genetic database for each breeding area is being developed to match up wintering birds. The genetic distinctiveness of Canadian vs. Russian Ross's Gulls is also being determined. Preliminary genetic evidence suggests Ivory Gulls have a low level of diversity, indicating that there's been a population bottleneck. To resolve population structure sequencing of additional base-pairs is underway.
Evidence for recent range expansion
of Alcataenia longicervica (Eucestoda:
Dilepididae) parasitic in murres (Uria spp.,
Alcidae) into the North Atlantic The geographic distributions of endoparasites can elucidate important, and otherwise hidden, aspects of the biology of their hosts. Alcataenia comprises a host specific genus of intestinal parasites restricted to the auks (Alcidae) and gulls (Laridae). Alcataenia meinertzhageni and Alcataenia armillaris have been collected from Thick-billed Murres (Uria lomvia) and Common Murres (Uria aalge) from various localities in the North Pacific and North Atlantic. One species, Alcataenia longicervica was described in murres from the North Pacific Basin and has been regarded as endemic to that region. We provide new geographic records of this cestode from the Northwest Atlantic and suggest that the species range may have expanded as a result of contemporary changes in the distribution and abundance of euphausiid crustaceans that serve as intermediate hosts.
Population Viability of Arctic Terns
Nesting in the Gulf of Maine Arctic Tern colonies in the Gulf of Maine are concentrated on a few islands. We used a capture-mark-recapture analysis of banded individuals (1999-2003) to develop and examine estimates of survival and dispersal. These data and estimates of productivity from 1995 to 2004 were used to examine the viability of the population. Results indicate that under current trends, the regional population is projected to reach twice the current number of terns nesting in the region within the next 10 years. If survival decreases or is lower, then regional population will increase, but the distribution of terns on the islands will change.
Band re-sighting error rates:
implications for project managers and seabird conservation For more than 100 years, researchers have been using banding and marking techniques to study the survival and movements of wildlife. Despite the large-scale and almost worldwide use of bird bands, no studies have addressed the issue of band re-sighting error directly. Therefore, I developed an experimental protocol to test for patterns of error during band reading. Here I discuss the results of concurrent field observations of banded Razorbills under live conditions and controlled experimental viewing of Razorbill bands at known distances.
Digiscoping - the usefulness of
digital imaging in ornithological research With the incredible advances in digital cameras, and the decrease in price, we make the case that when conducting research, digital cameras should be as essential as binoculars and a field book. We provide evidence from the past summer on Machias Seal Island that show the great value of digital cameras and video recorders, and the art of digiscoping in a seabird colony.
Understanding the environmental
impacts from offshore oil and gas activities in the NW Atlantic: Issues
around access to data. Offshore oil and gas is an expanding industry, particularly in eastern Canada. The northwest Atlantic poses unique and extreme environmental conditions compared to the majority of areas (e.g., Gulf of Mexico) previously developed for offshore oil and gas. These circumstances require recognition of the uncertainties around predicting environmental impacts and an investment in research which enhances our understanding of the environmental impacts specific to this region. The environmental impact assessment process provides a venue in which environmental impacts from offshore oil & gas are predicted. I examine how two types of pollution (oil spills and chronic oil pollution from platform discharges) were addressed in the environmental assessments for three oil production projects on the Grand Banks and the availability of relevant data. I discuss how the Canada-Newfoundland Atlantic Implementation Accord Act, in some cases, prevents a scientific assessment of the environmental impacts of the offshore industry; and place this issue in a broader legislative context.
The Parks Canada Cooperative Study
unit Concept - Atlantic Canada Connections Overview [no abstract provided]
Boreal songbird nest success in
heterogeneous landscapes of northern Newfoundland Heterogeneity of habitat and its effects on demographic parameters of animals have been important research foci because of recent increases in anthropogenic alteration of habitat. One component of a multifaceted study in the Gros Morne Greater Ecosystem, Newfoundland, is studying nest success of boreal songbirds in naturally occurring and anthropogenically-created heterogeneous landscapes. During the summers of 2004 and 2005, 170 nests of 12 species were located and monitored. Data are being analysed to measure daily nest survival of boreal songbirds to test if there is an influence of landscape type (natural or anthropogenic). Summary statistics will be presented. Independent effects of habitat
amount and fragmentation on songbirds in a forest mosaic: an
organism-based approach The degree to which spatial patterns influence the dynamics and distribution of populations is a central question in ecology. This question is even more pressing in the context of rapid habitat loss and fragmentation which threaten global biodiversity. However, the relative influence of habitat loss and landscape fragmentation - the spatial patterning of remaining habitat - remains unclear. If landscape pattern affects population size, managers may be able to design landscapes that mitigate habitat loss. We present the results of a mensurative experiment designed to test four habitat loss versus fragmentation hypotheses. Unlike previous studies, we measured landscape structure using quantitative, spatially explicit habitat distribution models previously developed for two species: blackburnian warbler (Dendroica fusca) and ovenbird (Seiurus aurocapillus). We used a stratified sampling design that reduced the confounding of habitat amount and fragmentation variables. Occurrence and reoccurrence of both species were strongly influenced by characteristics at scales greater than the individual territory, indicating little support for the random sample hypothesis. However, the type and spatial extent of landscape influence differed. Both occurrence and reoccurrence of Blackburnian Warblers were influenced by the amount of poor-quality matrix at 300 and 2000 m spatial extents. The occurrence and reoccurrence of Ovenbirds depended on a landscape pattern variable - patch size - but only in cases when patches were isolated. These results support the hypothesis that landscape pattern is important for some species only when the amount of suitable habitat is low. Though theoretical models have predicted such an interaction between landcape fragmentation and composition, to our knowledge this is the first study to report empirical evidence of such non-linear fragmentation effects. Defining landscapes quantitatively from an organism-based perspective may increase power to detect fragmentation effects, particularly in forest mosaics where boundaries between patches and matrix are ambiguous. Our results indicate that manipulating landscape pattern may reduce negative impacts of habitat loss for Ovenbird, but not Blackburnian Warbler. We emphasize that most variance in the occurrence of both species was explained by local scale or landscape composition variables rather than variables reflecting landscape pattern.
Apparent survival and population
viability of a forest bird indicator species in relation to
landscape-scale forest management The objective of this research is to determine the influence of a reduction of mature forest at the landscape scale caused forest management on the apparent survival of two forest bird species (Blackburnian Warbler [Dendroica fusca] and Black-throated Green Warbler [D. virens]). We captured and colour-banded these species in multiple years (2004 and 2005) to gain measures of age, morphometrics, and return rates used to estimate apparent annual and within-season survival in Program MARK. Data collected will be used to develop Population Viability Analyses (PVA) models for the two focal species in 2006.
Bird research in Kouchibouguac
National Park [no abstract provided]
Songbird movement: concepts,
ecological relevance, and research approaches Songbirds are capable of making regular large-scale movements, and movement patterns can affect a variety of demographic parameters. In cooperation with Parks Canada and Corner Brook Pulp and Paper, we have been conducting an intensive study of boreal forest songbird movement in western Newfoundland since the summer of 2003. Here we provide a conceptual overview of movement behaviour, review the ecological importance of various types of movement, and discuss direct and indirect methods we are using to quantifying songbird movement. In particular, we discuss our efforts to investigate both the influence of forest management on songbird movement, and to relate movement patterns to demographics.
Movement patterns and space use by
two boreal songbirds in a patchy forest during the breeding season. The boreal forest biome is critical breeding ground for nearly 300 avian species, yet over 30% of Canada's boreal has been designated for logging, energy, and other development. Levels of fragmentation induced by anthropogenic activities may disrupt landscape connectivity such that organisms cannot readily move to access much needed resources. During the breeding seasons of 2004 and 2005 in northern Newfoundland, we used radio telemetry to characterize movements of male blackpoll warblers and northern waterthrush as a function of the level of natural versus anthropogenic (by clearcut logging) heterogeneity. Preliminary analyses of trajectory data and space use will be presented.
Movements, Habitat Use, and Survival
of Juvenile Songbirds in Managed Boreal Forests of Northwestern
Newfoundland To date, studies of boreal songbird movement, habitat use, and subsequent survival have focused on adults during the breeding period. As a result, fledgling behaviours and their relationships to movement and survival prior to migration are poorly understood. In an effort to fill this knowledge gap, we used radio-telemetry to study movement, habitat use, and survival of juvenile Blackpoll(Dendroica striata) and Myrtlewarblers (D. coronata) during the post-breeding period in a managed boreal forest of northwestern Newfoundland. Preliminary results regarding movement (distance, displacement, rate, and direction) and survival will be presented and future research ideas will be discussed.
Factors affecting counts of
nocturnal flight calls of fall migrating passerines Avian nocturnal flight calls (nf-calls) serve to maintain and elicit additional migrants to migration flocks. Little is known about nf-calling rates, and therefore it's difficult to use these data to determine numbers of birds aloft. Radar studies have shown that the timing of peak numbers of nf-calls does not always correspond to the peak number of birds aloft. A number of environmental factors may affect the calling rates of migrants. We compared radar data and microphone recordings of fall migration to determine the influence of visibility, wind direction, numbers of migrants and time of night on numbers of nf-calls detected.
The influence of local weather and
climatic factors on the migratory decisions of songbirds in Atlantic
Canada: a preliminary assessment Migration is an energetically expensive behaviour with costs that likely increase in unfavourable environmental conditions. As a consequence, temperate-breeding songbirds may face an elevated risk from potential increases in the variability of weather caused by climatic changes. We are using multi-state mark-recapture analyses and other likelihood-based models to investigate the stopover decisions of passerines in Atlantic Canada in relation to current weather conditions and to birds' migratory fat loads. We further plan to determine how the influence of weather may differ across years, among stopover sites, between migration seasons, and among species. Such insight into migration decisions is critical for making proper assessments of conservation risks.
Local-scale movements of birds at
windfarms -a radar study. I am presently planning a field study which will involve using multiple radars to examine fine-scale bird movements in relation to topography, weather and wind. This information will hopefully feed into models that can better asses the placement of wind farms. Another component will involve examining specific bird behaviour at a wind farm in relation to different weather conditions and lighting.
Avian Flu in Canada: waterfowl
reservoirs, transmission potential and management The Avian Influenza A Virus has recently emerged as a highly pathogenic virus causing mortality in humans, domestic animals and wildlife. The virus is widespread in ducks and shorebirds, which are regarded as reservoirs of many subtypes of the virus. The movements of migratory species disseminate the virus over wide geographic areas. Co-feeding of domestic and wild waterbirds in Asia has facilitated the transfer of the virus into the poultry industry. Canadian waterfowl are known to harbor many subtypes of the virus and the threat of an outbreak exists. The Canadian plan to deal with a pandemic addresses the question of human treatment protocols at the event of an outbreak. Fecal discharge and discards from the poultry industry may enhance the transmission of the virus between domestic and wild birds. The processing, discharge and disposal of poultry refuse should be carefully re-evaluated and measures taken to minimize contact between these by-products and wildlife.
East coast eider initiative Ducks Unlimited Canada's Eider Initiative is a 5-year research initiative. The goal of this research is to develop a population model to guide Common Eider (Somateria mollissima dresseri) harvest regulations and management decisions. To reach this goal, we are using capture-mark-recapture techniques to estimate survival parameters. During 2004-05 we captured 2,398 duckling (1 d old), 242 prefledged juvenile (>30 d old), and 676 adult Common Eiders. The upcoming 2006 field season will provide the third year of mark-recapture data, permitting our first estimates of adult survival. This research project is ongoing.
Population status of Semipalmated
Sandpipers based on mark-recapture and morphometrics of migrating birds
in the upper Bay of Fundy Annually, 100,000s of the Semipalmated Sandpipers Calidris pusilla stopover in the upper Bay of Fundy and double their body mass feeding on Corophium before undertaking a nonstop migration to South America. Over 13 field seasons from 1981 to 2005, 33,872 individuals have been captured and banded along the shore of Johnson's Mills, New Brunswick, in the upper Bay of Fundy. About half of these birds were measured (bill length, wing length and body mass). Banded birds were recaptured in subsequent years, which allowed for the calculation of annual mark-recapture estimates of the source population of the Johnson's Mills birds. Our estimates suggest a decline from about 800,000 birds in 1982 to about 260,000 in 2004, or about 5% per annum, in keeping with previous reports of the general population status for this species. Mean bill length of measured birds declined over the course of the study, perhaps reflecting a disproportionate loss of long-billed individuals known to breed in the more eastern parts of the species' range. The accuracy of our population estimates relies on how well the assumptions of mark-recapture methodology were achieved. We have evidence that at least one such assumption- that of independence of individual recapture probabilities- may not have been met. Forty groups of 2-5 five birds, each captured in the same trap on the same day, were recaptured together, either in the year of banding (n = 30), in the next year (n = 8) or two years after (n = 2). Further tests will be needed to determine if these frequencies are greater than expected by chance, but the observation suggests the possibility that some Semipalmated Sandpipers associate in groups, which may persist within and between years and therefore across quite different life-stages of migration, over-wintering and breeding.
Movement and habitat use of
Semipalmated Sandpipers migrating through Shepody Bay Distribution of migrating birds among foraging and roost sites around Shepody Bay has changed in recent years. To assess movements, SESAs were radio-tracked in 2004 and 2005. Major differences were observed in SESA habitat use between the two years. In 2004, very little movement was detected with the majority of birds remaining on one site. In 2005, the SESAs were more mobile, using several different sites to forage and roost. The differences may be due to a change in Corophium densities on some sites, and an increase in predator attacks. |