Centre For Wildlife Ecology
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I supervise an array of studies addressing conservation issues that affect waterbirds in arctic and subarctic habitats along the Pacific coast. The issues, species, populations, and, often, individuals being studied are shared concerns of the Centre for Wildlife Ecology, the Canadian Wildlife Service, and collaborators at higher latitudes. | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Surf and White-Winged Scoter Populations and Shellfish Aquaculture | |||||||||||||||||||||||||||||||||||||||||||||||||||
I am involved in a collaborative program studying scoters in coastal British Columbia, involving CWS, and an array of agency, university, and industry partners. This research addresses interactions between wintering surf and white-winged scoter populations and shellfish aquaculture, which are concentrated in similar areas and require similar resources. To address this issue, we need to understand the processes by which scoters choose foraging patches, the attributes of habitat patches that influence scoter foraging decisions, the scale over which scoters forage, the effects of scoter foraging on shellfish resources, the effects of variation in prey densities and types on scoter foraging and distribution, and the population-level demographic consequences of these interactions. In turn, this will generate data that will (1) indicate the mechanisms by which conflicts or benefits of the shellfish industry could occur, (2) evaluate the population-level effects of the shellfish industry, and (3) predict effects of current and projected levels of shellfish industry activity. This project includes the thesis work of MSc students Tyler Lewis (defending fall 2005) and Molly Kirk. For more information about this and associated projects, check the Sustainable Shellfish Aquaculature webpage. | |||||||||||||||||||||||||||||||||||||||||||||||||||
©Bates Littlehales | |||||||||||||||||||||||||||||||||||||||||||||||||||
Sea Ducks and the Exxon Valdez Oil Spill | |||||||||||||||||||||||||||||||||||||||||||||||||||
I am continuing research initiated in 1995 addressing population-level responses of sea ducks (particularly harlequin ducks and Barrow’s goldeneyes) to the 1989 oil spill in Alaska. In collaboration with a research team of agency and university partners, we have documented that these sea ducks continued to be exposed to residual oil for more than a decade following the spill. Further, harlequin ducks have shown long-term demographic consequences of the oil spill, in contrast to the conventional wisdom that oil spill effects are short-lived for bird populations. These findings have important implications for understanding effects of large spills (e.g., Nestucca), low-level chronic releases, such as in boat harbors, and risks of large-scale industry (e.g., oil and gas exploration in northern BC waters). Current studies are examining the links between oil exposure and demography in harlequin ducks, including both field and captive approaches. Ongoing field work includes capture, biosampling, and radio-marking harlequin ducks to document, on individual and population-level bases, the relationship between exposure to oil and subsequent winter survival. Captive studies at the Alaska SeaLife Center involve exploration of the physiological and behavioural responses to oil exposure, as potential mechanisms that would lead to observed survival reductions in wild harlequin ducks in oiled areas. | |||||||||||||||||||||||||||||||||||||||||||||||||||
© John Hyde | |||||||||||||||||||||||||||||||||||||||||||||||||||
Surf Scoter Spring Migration Habitats
Although Pacific Surf Scoters have been the subject of a growing body of research during winter, little is known about their spring migration ecology. Spring migration conditions have important implications for waterfowl productivity, and habitat conditions and nutrient reserve levels during spring migration have been implicated as important factors affecting broad-scale and long-term population declines. An important part of establishing connectivity and cross-seasonal effects through the annual cycle is the determination of distributions and habitat requirements at critical annual cycle stages. Satellite and VHF transmitters have been deployed on Surf Scoters across their Pacific wintering range, including Baja California Mexico, San Francisco Bay, Puget Sound, and the Strait of Georgia. As part of a collaborative study of Surf Scoter spring migration ecology, we are using a combination of satellite telemetry, radio telemetry, and surveys to document spring distributions of Pacific Surf Scoters throughout southeast Alaska and the northern BC coast, with a focus on identifying important stopover areas and associated habitat attributes, particularly herring spawning sites. This work is led by MSc student Erika Lok, who has completed the first of 2 field seasons. |
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Red-throated Loon Provisioning | |||||||||||||||||||||||||||||||||||||||||||||||||||
Numbers of red-throated loons have declined by over 50% in recent decades. Jeff Ball (M.Sc. student; graduated fall 2004) considered the underlying causes of this population change by addressing the hypothesis that changes in forage fish quantity or quality have constrained the ability of parents to adequately provision chicks, resulting in subsequent depression of recruitment. Jeff found that, during 2002-2003, moderate-to-low energy fishes dominated the prey community. This potentially constrained parental ability to meet brood attendance and energy requirements. Two-chick broods were not fed at higher rates than single-chick broods and all two-chick broods were reduced, apparently from starvation of the younger sibling. Energy consumption also influenced first-hatched chick survival during week one, when both provisioning effort and attendance requirements were high. For chicks surviving this early period, sex influenced growth variation more than energy consumption. Overall, survival and growth performance measures were poorer than published findings, suggesting poor foraging conditions were a mechanism limiting productivity. | |||||||||||||||||||||||||||||||||||||||||||||||||||
©Yann Kobleinsson | |||||||||||||||||||||||||||||||||||||||||||||||||||
Greater Scaup Nutrition and Timing of Nesting | |||||||||||||||||||||||||||||||||||||||||||||||||||
Another project initiated in collaboration with the U.S. Geological Survey addresses the relationships of nutrition and physiology to timing of reproduction by greater scaup in coastal Alaska. M.Sc. student Kristen Gorman (graduated spring 2005) led the work. Specific project goals included determining when and where energy and nutrients needed for clutch formation are acquired, the effect of nutritional status on timing of reproduction, and correspondence of circulating levels of yolk precursers with reproductive status. Kristen found that Greater Scaup females employ an unusual strategy of nutrient acquisition and allocation for clutch formation, in comparison to other ducks. They store nutrients on breeding areas, delay initiation of clutch formation under nutrient storage thresholds are achieved, but paradoxically do not invest stored nutrients into eggs. Instead, nutrient stores are likely used during incubation, reducing the need for incubation breaks and the corresponding increase in nest predation risk. Kristen also demonstrated, for the first time, the utility of using circulating levels of plasma yolk precursors as an indicator of reproductive status in waterfowl. | |||||||||||||||||||||||||||||||||||||||||||||||||||
©Dr. K.T. Rogers, California Academy of Sciences | |||||||||||||||||||||||||||||||||||||||||||||||||||
Harlequin Duck Breeding Densities and Productivity | |||||||||||||||||||||||||||||||||||||||||||||||||||
This project is designed to address, on a regional scale, the factors that influence harlequin duck distribution and productivity in the southern Coast Mountains of British Columbia. This research is supported primarily by BCHydro’s Bridge Coastal Fish and Wildlife Restoration Program and provides the scientific background necessary to understand how variation in habitat (including that related to hydroelectric operations and other human activity) affects harlequin ducks, and prescribe concrete mitigation or restoration activities that would improve harlequin duck productivity. A primary objective of the research is to develop models describing the relationship between harlequin duck distribution and habitat attributes (for example, stream gradient, width, substrate, vegetation, prey availability, fish presence, etc) at a regional scale. In addition to the broad-scale description of patterns in harlequin duck distribution and productivity, we are addressing 2 specific mechanisms that we consider critically important for understanding how breeding habitat (and changes to that habitat) influence harlequin duck productivity: (1) does foraging on breeding streams constitute an important part of the energy and nutrients required for clutch formation? and (2) does fish abundance influence the availability of harlequin duck invertebrate prey (through either effects on invertebrate abundance or behavior)? Answers to these questions will provide insight into links between food, tropic interactions, and subsequent harlequin duck productivity. These questions form the primary thesis directions for MSc candidates Jeanine Bond and Sunny LeBourdais, respectively. | |||||||||||||||||||||||||||||||||||||||||||||||||||
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