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Protecting species by identifying threats throughout their full life cycle

Migratory animals are under a suite of selective pressures that vary between location and season, and they must be able to thrive in multiple habitats. What happens during one period of the annual cycle can carry over and affect subsequent periods. Unfortunately, a lot of research and conservation efforts focus on only one period of an animal’s life cycle.

Effective management

To understand why a migratory species might be endangered requires complete information on ecology and threats throughout the entire annual cycle. It is for this reason that migratory connectivity information is so important to solving difficult environmental issues from climate change to the spread of infectious disease.

Our ultimate goal is for these data to be applied to real-world problems and for land managers to incorporate migratory connectivity information into conservation plans.

Conservation issues and research questions

  • Basic information: annual distribution, abundance, and habitat
  • Connecting populations: breeding populations with their wintering location and visa versa
  • Seasonal interactions: effect of winter events on migration and breeding and vice versa
  • Climate change: changing distributions, changing abundance, changing movement
  • Disease: predicting the spread of infectious disease
  • Urbanization: habitat change and pollution can have carry-over effects throughout the annual cycle
  • Energy: placement of wind towers to avoid migratory pathways and carry-over effects
  • Toxicology: where animals pick up pesticides and contaminants
  • Invasive species: altered ecosystems and natural communities can have carry-over effects
  • Illegal take: molecular markers to help track and prosecute illegal take
  • Air strikes: anticipating bird-aircraft collisions

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Avian  research  priorities

1. Connectivity Gaps

  • Citizen science: identify migratory connectivity to facilitate joint modeling of Breeding Bird Survey and Christmas Bird Count data
  • Migration and staging: identify connectivity between breeding and migration areas and between wintering and migration areas
  • Natal dispersal: needed for demographic modeling

2. Mark-recapture

  • Geo-locators: use MAPS and MoSI stations to test connectivity hypotheses
  • Geo-locators: test accuracy in realistic forest/shrub habitat
  • Transmitter network: coordinate network of stations to deploy transmitters and sample tissues for genetic and isotope analyses

3. Tracking

  • GPS: more data for broader range of species and migratory routes
  • GPS: although the appropriate size does not yet exist, deploy tags on a handful of small-sized species to launch further research and development
  • Radio/VHF: develop datalogger infrastructure to cover broader range of seasons, locations, and species
  • Smaller transmitters and receivers (GPS and radio)
  • Economize tracking technology (more affordable)

4. Isotopic Analyses

  • Isoscape maps: improve and refine
  • Deuterium isoscape map: mine existing GNIP and related databases for precipitation data to refine North American map
  • Avian origin maps: develop web-based tool to create probability maps of origin based on isotope data
  • Isotope database: for avian tissues (even if based on only published studies)
  • Tissue collection: continue collections from MAPS and MoSI stations

5. Genetic Work

  • Genetic markers: develop population-specific markers for all North American species
  • Sentinel species: identify potential species for genetic tracking

6. Mapping, Modeling, and Analysis

  • Full life-cycle conservation model: identify limiting factors, seasonal connectivity, causes of decline, and conservation strategy
  • Satellite-derived environmental data (e.g. from NASA TOPS): correlate with connectivity data (tracking, isotopic, or genetic) to understand effect of climate, primary productivity, and vegetation phenology
  • Physiological and ecological niche models: to improve ability to forecast movement
  • Habitat models: estimate migratory, breeding, and overwintering habitat for priority species
  • Migration models: migratory movement through USFWS reserves and other locations, including subspecies
  • Morphology maps: use MAPS and MoSI data to create age-specific and sex-specific maps showing spatial distribution of morphology measurements to provide hypotheses of migratory connectivity
  • Vitality maps: use Bayesian hierarchical spatial Jolly-Seber models with MAPS data to create maps of lambda and recruitment parameters to identify knowledge gaps and suggest proximate demographic causes of population trends (this has already been done using Cormack-Jolly-Seber models)
  • Variation in vitality rates: model temporal variation using MAPS data (productivity, adult apparent survival, recruitment) as a function of late winter precipitation to determine areas where winter weather is correlated with productivity or survival
  • International coordination of environmental data: merge geographic and environmental data layers across international borders
  • Migration and connectivity database: compile existing data on population-level variation in migration and connectivity (e.g. subspecies specimen data)
  • Migration models: link migratory routes to landcover and land use data to understand migratory barriers or attractants

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  1. Haig, S.M., D.W. Mehlman, and L.W. Oring. 1998. Avian movements and wetland connectivity in landscape conservation. Conservation Biology 12: 749-758.
  2. Marra, P. P., C. E. Studds and M. Webster. 2010. Migratory Connectivity. Encyclopedia of Animal Behavior. Eds. Breed & Moore, Academic Press, Oxford Press.
  3. Marra, P.P., D.R. Norris, S.M. Haig, M. Webster, and A. Royle. 2006. Migratory Connectivity. Maintaining Connections for Nature. Kevin Crooks and Sanjayan Muttulingam (Eds.). Oxford University Press.
  4. Marra, P. P., K. A. Hobson, and R.T. Holmes. 1998. Linking winter and summer events in a migratory bird using stable carbon isotopes. Science 282: 1884-1886
  5. Webster, M.S., P.P. Marra, S.M. Haig, S. Bensch, and R.T. Holmes. 2002. Links between worlds: unraveling migratory connectivity. Trends in Ecology and Evolution 17: 76-83.

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HOME | connecting populations | seasonal interactions | climate change | disease | urbanization

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