|
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 |
|
HUGH JOHN FLEMMING CENTRE, FREDERICTON, NB (UNB) 2004 Explaining
American marten (Martes americana) habitat
selection The American marten is known as an indicator species for landscape integrity because of its ³preference² for old-growth coniferous forests (Buskirk and Ruggiero 1994, Fecske et al. 2002). Most eastern marten populations, however, have also been found to use mixed and deciduous stands disproportionately more than is available (Soutiere 1979, Payer and Harrison 2002, Potvin et al. 1999, Mech and Rogers 1977). Many researchers have been interested in the habitat suitability for the American marten. Though much is already known about this species ecology, there are still big uncertainties about their habitat selection Many studies have addressed tern diet and breeding success, but it is still unknown where they forage for their prey or how Arctic and Common Terns differ in their foraging habitat. During the summer of 2004 we began a radio tracking project to determine where breeding terns feed around Machias Seal Island. This field season served as an exploratory year. Preliminary data suggests that the common terns are foraging near the Maine coast and immediately around MSI, while arctic terns are traveling further offshore to feed. This implies that these two closely related species differ in where they forage on their breeding grounds.
Encounter, Survival, and Movement
Probabilities from an Atlantic Puffin (Fratercula arctica)
Metapopulation Several weaknesses in our understanding of
long-lived animal populations have persistence mainly due to a
prevalence of single local population research at the expense of
multi-site studies. We performed a mark-resight analysis using 2,050
Atlantic puffins (Fratercula arctica) banded as chicks on four colonies
over 24 years in the Gulf of Maine. Resighting probabilities were
extremely variable making explicit their contribution to data
structure. Survival probabilities increased to a peak at age five then
declined, possibly due to failing bands. Natal dispersal, and
consequently philopatry, varied extensively among colonies. Colony
numbers were apparently a function of movement but not survival. Using local-scale relationships
between weather variables and migration patterns to predict relative
vulnerabilities of songbirds to future climate change Despite the intense attention given to climate change and its biological implications in recent years, it is difficult to determine which particular species or groups of migratory birds may be particularly vulnerable. We propose to evaluate the relative vulnerability of passerines that migrate through Atlantic Canada to projected future climate scenarios by relating two types of information on the migrants (mark-recapture data and daily censuses) to local weather data. Modeled relationships between small-scale weather factors and migration decisions (arrival at and departure from stopover sites) would then be incorporated into climate projections to predict relative effects on different species and groups.
Differences in breeding and
wintering diets of sympatrically nesting terns determined by
stable-carbon and nitrogen isotope analysis Common (Sterna hirundo) and Arctic Terns (S. paradisaea) are closely-related seabirds with overlapping breeding ranges, but different migration routes and wintering grounds. We wanted to determine how terns altered their diets during these two phases of their life-cycle. Stable-isotopes of carbon [13C/12C] and nitrogen [15N/14N] of feathers, egg components and fish prey were used to compare their diets at different temporal scales. Results show that Common and Arctic Terns have similar diets on their shared breeding grounds, but completely different diets on the wintering grounds. We provide further evidence that Common and Arctic Terns use exogenous energy reserves for egg production. Fine-scale movement and the effects
of pool characteristics on the abundance of the peatland dragonfly Leucorrhinia
hudsonica in western Newfoundland Past studies have shown that fine-scale decisions can influence the broader scale pattern of population dynamics. I conducted a mark-release-recapture experiment on adult male L. hudsonica in three peatlands. Generalized linear models were used to model the physical pool characteristics on dragonfly abundance. Results indicate that the size of the pool was the main co-variate that affected the number of L. hudsonica found at a particular pool. Quantile-quantile plots also show that distances that dragonflies were found to move within a peatland are not random.
Spatial ecology and movement of
resident birds in a managed forest landscape of western Newfoundland Despite growing interest in the effects of
landscape structure and forestry on the dynamics of boreal birds,
little is known about the spatial ecology of resident species among
seasons. My research will be conducted in the Greater Gros Morne
Ecosystem (GGME) of western Newfoundland, where spruce-fir forest is
increasingly fragmented by industrial forestry. I plan to investigate
resident bird movement across naturally patchy and harvested landscapes
to determine how residents respond to stand age and habitat
configuration, according to season. Resident movement may incorporate
larger spatial scales than previous GGME studies. Results will
compliment the ongoing development of GGME management models. Razorbill (Alca torda)
survival and dispersal in Atlantic Canada Recent surveys of Razorbill populations in Atlantic Canada have shown an increasing trend. Although survival estimates are not available for most colonies within this region, it is thought that this increase in numbers may be due to high adult survival. A questions of significant importance then becomes is high adult survival enough to account for an almost doubling of some populations in only 15 years, given that the species typically exhibits low reproductive success? As a result, I am collaborating with the Canadian Wildlife Service and University of New Brunswick to examine the survival and dispersal of the Razorbill at three different colonies across their breeding range.
Boreal songbird nest success in
naturally and anthropogenically fragmented landscapes Fragmentation of natural habitat can have significant influence on species demography. A multifaceted study is being conducted on boreal songbirds in the Greater Gros Morne Ecosystem to investigate the effects that logging has on passerine demographics and movement. From June to August 2004, nest success of 12 species was recorded in clear cut and natural sites. A total of 80 nests were monitored. Data will be analysed to determine if fragment type (natural or anthropogenic) affects nesting success. Preliminary results will be presented and methods of analysis will be addressed.
Are Arctic Terns in the Gulf of
Maine and Bay of Fundy part of a regional metapopulation? The study of metapopulations has become a common approach in population biology. Levins (1969; 1970) first suggested the term metapopulation dynamics in relation to invertebrate migration and extinction rates. There has been considerable development of the subject through theoretical modeling, and an increasing number of studies are testing models using empirical data. Arctic Terns nesting on islands in the Gulf of Maine and Atlantic Canada offer the opportunity to examine the dynamics of a regional population of nesting seabirds to determine whether these birds exhibit the characteristics of a "classical" Levins metapopulation or if each island colony acts as its own independent population. We hypothesized that most terns would return to the islands where they were first captured, but that movement of terns among islands would explain some of the annual variation in nesting populations. We found that movement can explain some, but not all, of the variation. Differing survival rates and reproductive success per island colony also play a role in the variation.
The world according to Weimerskirch
- linking seabirds with their marine environment ACWERN's seabird program explores the links
between seabird populations and changes in their environment. These
links are complex, and the challenge is to select productive Before the arrival of European settlers, the Chimney Swift was associated with old growth forests, when large hollow trees were abundant and their main source of nesting and roosting sites. Today, the Chimney Swift is most often associated with urban and suburban zones, nesting primarily in chimneys. Numbers of Chimney Swift in Canada have been decreasing for the last 36 years and the situation continues to worsen. The main reason for this decline appears to be the lost of suitable breeding sites, caused by the modification, closure or destruction of suitable chimneys.
Science Partnership Opportunities in
Atlantic Canada's National Parks Parks Canada is charged with maintaining the ecological integrity of its national parks. To achieve this, the organization seeks to permit natural processes to occur unimpeded and to retain native species in viable populations. Clearly, this cannot occur in small protected areas alone. To work, national parks must be imbedded in ecologically sustainable landscapes. But, what is an ecologically sustainable landscape? In order to make sound recommendations, Parks Canada must support original research in this area, and have a comprehensive and sensitive ecosystem monitoring program to assess our progress along the way. In addition, we need to engage in special management initiatives so that we do not lose biodiversity while we are figuring this all out. Hence, major opportunities for science partnerships are in the developing fields of conservation biology and landscape ecology, developing and testing long-term monitoring programs, and helping to conserve species at risk. The presentation will outline current initiatives and future projects.
Breeding pair surveys indicate that continental numbers of scoters have declined by more than 50%. Surf Scoters are one of the least studied ducks in North America and reliable information on population status, structure or dynamics do not exist, and estimates of vital rates are lacking. We propose to measure vital rates, affiliations between moulting and harvest areas, screen birds for parasites and contaminants, and study moulting ecology of Surf Scoters. In 2004, we conducted a feasibility study where we developed capture techniques and working knowledge of a potential study area in coastal Labrador. We also report on our preliminary results. The impact of Laying Date on Egg
Size, Growth and Breeding Success of Razorbills breeding on Machias
Seal Island Status and conservation of eelgrass (Zostera
marina) in Eastern Canada Eelgrass (Zostera marina) has been widely recognized as an important component of coastal ecosystems in Eastern Canada. Regional surveys to monitor changes in eelgrass distribution and abundance do not yet exist. Available information from specific study areas provides consistent evidence of a wide spread decline in eelgrass distribution and abundance in the Maritime Provinces. I will present information from a recent workshop on eelgrass and discuss future research opportunities.
Long- and short-term seabird
research projects in Atlantic Canada: how do they fit in with
conservation priorities? Seabird research in Atlantic Canada is focused at
a few major sites and populations (Gannet Islands, Witless Bay, Machias
Seal Island), but how is it relevant to conservation priorities?
Long-term measurement of survival is producing valuable information on
climate variability and anthropogenic sources of mortality and data
from more sites and species would be extremely valuable. Seabird
breeding success is high and may
Movements of boreal songbirds in
naturally patchy and anthropogenically fragmented forests In order to successfully model connectivity for a given species, actual rates of movement and mortality during these forays must be considered. For forest-dependent songbirds moving through fragmented landscapes, few data of this kind are available. In summer 2004, we used radiotelemetry to characterize male songbird movement in naturally patchy and clear-cut landscapes. Preliminary analyses of trajectory data will be presented. Data will later be analyzed using a state-space model approach that will predict songbird movement across the landscape. Forest managers may use the model when planning future harvesting operations so that connectivity will be maintained for boreal passerines.
Norway rats as predators of Least
Auklets at Kiska Island, Alaska: new insights from stable isotope
analysis The objective of this study was to assess the impacts of introduced Norway rats on Least Auklets breeding at Kiska Island, Alaska. We have used stable isotope analysis to reconstruct and compare the diet of Norway rats both on (Sirius Point) and off (Christine Lake) the auklet colony to further investigate the impacts of this introduced species. Our results revealed that d13C and d15N differ significantly between locations, rats at Sirius Point feed at a higher trophic level than those at Christine Lake and dietary preferences of individuals remained constant throughout our sampling period.
Tree Species Selection and Use by
Foraging Insectivorous Passerines in a Forest Landscape American beech (Fagus grandifolia) was selected out of proportion to its abundance by three warbler species and one flycatcher during foraging bouts. Yellow birch (Betula alleghaniensis) was usually avoided. Arthropod density and diversity did not explain the selective foraging behaviour in most cases. Tree species' morphology related to foraging efficiency probably explains most of the foraging behaviour patterns. American beech basal area predicted landscape patterns of distribution of black-throated green warbler (Dendroica virens), northern parula (Parula americana), and magnolia warbler (Dendroica magnolia). American beech basal area was also a significant predictor of avian productivity in a companion study.
The effect of invasive ants on
Tristram's storm-petrel in the Northwest Hawaiian Islands The ability of invasive ants to negatively affect the breeding success of birds is a crucial issue in island conservation. Invasive ants are established on all Northwest Hawaiian Islands, yet no study has yet to investigate their effects on the native avifauna. From November 2003 to June 2004 efforts were made to document the effects of invasive ants on the nesting success of 116 Tristram's storm-petrel (Oceanodroma tristrami) breeding pairs on Laysan Island, Northwest Hawaiian Islands. Fledging success was reasonable (32%, n = 53) despite high populations of ants in the study area. Intra-seasonal and inter-seasonal
variability in feeding of four Atlantic seabirds We have ten years of feeding data collected for four species of seabirds breeding on Machias Seal Island (MSI), New Brunswick. The focal species include two surface-feeding terns: Arctic Tern and Common Tern, and two pursuit-diving alcids: Atlantic Puffin and Razorbill. Previous work on MSI has shown poor weather to hinder the feeding and reproductive success of the surface-feeders, but not the pursuit-divers. 2004 was a cool summer with low-quality prey, resulting in a failed tern colony and an alcid colony with greatly reduced growth rates. The 2004 summer offers an ideal situation to compare how different natural history strategies shape reproductive success as food varies between summers and within seasons.
Avian Movement in Response to
Fragmented Landscapes of the Greater Gros Morne Ecosystem of Western
Newfoundland The landscape mosaic of the Main River Watershed of the Greater Gros Morne ecosystem, Western Newfoundland, is rapidly changing as a result of forestry operations in the area. Previous studies have documented landscape level effects in the movement of a variety of taxa. I plan on contributing to this knowledge base using birds. Specifically, I am interested in differences in response of resident species to natural ecotones and harvested edges, the response in avian movement at a greater spatial scale than has been previously been studied in the area, and the effect of landscape composition and connectivity on juvenile dispersal.
Comparisons Between Nightly Radar
Observations and Numbers of Birds Detected at a Migration Monitoring
Station Using a 3 cm conical radar, the nocturnal migration of passerines in southwestern Nova Scotia was observed during the autumn of 2003. We will take a descriptive look at these data, investigate temporal, altitudinal and directional attributes of avian migration, and make comparisons to numbers of migrants detected at a migration monitoring station, the Atlantic Bird Observatory. Advantages and enhancements that radar monitoring can bring to current monitoring efforts will be discussed.
Songbird movement in naturally
heterogeneous and harvested landscapes in western Newfoundland Movement is a process critical to population persistence and survival yet the movement patterns of many organisms are not well understood. In particular, it is not clear how highly mobile groups of organisms (such as songbirds) alter their movement patterns in response to landscape alteration. We examined the movement patterns of songbirds in response to complete landscape alteration (clearcutting) in the Main River watershed of western Newfoundland using mark-release-recapture methods. We compared movement distances of birds in naturally heterogeneous and clearcut landscapes to determine the influence of forest harvesting on these birds. Preliminary analyses show that movement is constrained in harvested landscapes relative to natural landscapes at small scales (<100 m) but there is more movement in harvested landscapes relative to natural landscapes at large scales (>100 m).
Conservation Genetics of Ivory Gull (Pagophila
eburnea) and Ross's Gull (Rhodostethia rosea) The Ivory gull is currently listed as "Vulnerable" under COSEWIC but its Canadian population has dropped 80% in recent years. This will likely result in it being up-listed to "Threatened" or "Endangered." Ross's gull is already classified as "Threatened." Very little research has been done with these birds and I will use genetic techniques to answer basic questions such as do different colonies interbreed and what the breeding colony source of birds over-wintering in Canada is. I will also look at the genetic diversity remaining in these birds. These pieces of information will be critical to developing a conservation strategy. Behavioral ecology and demography of
Atlantic puffins (Fratercula arctica) in Newfoundland and Labrador: a
study proposal Atlantic Puffins breed commonly at numerous sites in Newfoundland and Labrador, but apart from a few studies of breeding success little is known about their population parameters and responses to climate variability and anthropogenic mortality. I will quantify behavior, breeding and survival at two representative breeding colonies (Gannet Islands and Gull Island) where large marked populations have been followed since the mid-1990s. Survival rate is the key to understanding the major aspects of functional ecology and population dynamics of long-lived monogamous seabirds. Survival analysis and population modelling, with respect to Individual, group, environmental and survival covariates will be performed using Program MARK to address key questions about puffin behavioural ecology and demography.
The upper Bay of Fundy is a critical migratory stopover point for Semipalmated Sandpipers. Little is known about how these birds select foraging habitat and if they stay on single mudflats, or move within the region, during their approximate 2-week stay. We hypothesize that the main factors potentially influencing sandpiper movements and habitat use are: 1) abundance of their main prey C. volutator, 2) predation threats by raptors and 3) landscape. To assess movements and test the importance of these factors, we radio-tracked 20 sandpipers from both Shepody Bay and the Minas Basin in the summer of 2004. Movements of birds relative to our hypothesized factors will be discussed.
Validating the use of a key designed
to differentiate between murres and Razorbills based on wing
characteristics Thick-billed and Common Murres are legally hunted along the coasts of Newfoundland; Razorbills are also occasionally taken. As a first step towards implementing a species composition survey (SCS) from wing samples submitted by hunters, a key using wing characteristics was developed and subsequently tested. Inexperienced observers correctly aged 92-96% of wings based on the presence of worn secondary coverts, and usually classified the murre species correctly using two techniques: visual assessment of wing shape (83-85%) and a discriminant function based on two feather measurements (92-96%). These results suggest that it is possible to implement an SCS for auks using wing characteristics.
Predation danger and shorebird
conservation Most work on the evolutionary ecology of shorebird migration has focused on food and foraging, on the ecological and physiological demands of long flights, and how these factors interact. In this talk I'll focus on the danger posed by predators, and its importance in the behavioral and evolutionary ecology of shorebird migration. The general hypothesis is that the recovery of raptor populations in the Americas since restrictions on the use of DDT is increasing predation danger for shorebirds, and that migration patterns are changing as birds alter behavior to mitigate the danger. Our data reveal that reductions in migratory fuel load and stopover duration of western sandpipers (Calidris mauri) measured over two decades are associated with the recovery of peregrine falcons (Falco peregrinus). Recent analyses of shorebird census data in North America indicate generally declining trends during the 1980s and 1990s, raising concern about many of the species in this group. I consider the extent to which behavioral effects may be contributing to widespread downward trends in census numbers. Survival and population viability of
a forest bird indicator species, Blackburnian Warbler (Dendroica
fusca), in relation to landscape-scale forest management The objective of this research is to determine the influence of forest management at the landscape scale on the survival of two forest bird species, Blackburnian warbler (Dendroica fusca) and Black-throated green warbler (D. virens). Both of these neo-tropical migrant species are reported to be dependent on mature forest and are potentially affected by forest fragmentation with Blackburnian warblers being more sensitive to habitat alteration. We will capture and colour-band these species in multiple years to gain measures of age and annual survival. In 2004, we banded 101 Blackburnian warblers and 149 Black-throated green warblers and will continue banding and resighting in 2005, while resighting only in 2006. We are looking specifically at the two extremes of the forest-fragmentation/habitat loss gradient. |
Updated Nov 06