We are in a time of rapid global change. Habitat loss and degradation has occurred for thousands of years, but climate change is a relatively new stressor. A critical question for ecologists and conservational biologists at this juncture in history is:
Which species are most at risk of extinction?
We can broadly define species as specialist or generalist species. A specialist species occupies a narrow niche in order to benefit from otherwise unused resources and space. A generalist species occupies a much broader niche, benefitting from the flexibility in resource and space requirements. The specialist species "strategy" is successful in times of environmental stasis, but challenging, if not deadly, in times of rapid environmental change. It is for this reason that specialist species worldwide are declining at rapid rates.
Tidal marsh birds are specialist species that nest in the grass near the ground in a habitat that regularly floods. They are adapted to these conditions, but sea level rise presents a problem. Marshes are getting flooded more frequently and in greater magnitude.
This causes me to ask the following questions:
1. How are tidal marsh birds adapted to nest flooding?
2. Do these traits convey adaptive capacity as sea levels rapidly rise?
3. From these traits, which species is most at risk in the long-term?
Which have lead to more specific questions and projects below:
1. How are tidal marsh birds adapted to nest flooding?
2. Do these traits convey adaptive capacity as sea levels rapidly rise?
3. From these traits, which species is most at risk in the long-term?
Which have lead to more specific questions and projects below:
Saltmarsh Sparrows as an indicator species?
A lot of research has been completed on the Saltmarsh Sparrow, a tidal marsh endemic species that is rapidly declining from sea level rise and other factors. We often think that this species is signaling the future fate of other tidal marsh bird specialist species. Is it? How closely aligned are the causes of its decline with the demographics of other species?
I will be using demographic data from the SHARP collaboration (https://www.tidalmarshbirds.org) to understand:
1. Whether Saltmarsh Sparrow population growth across sites are positively correlated with nest success rates for Seaside Sparrows, Willets, and Clapper Rails
2. The underlying factors that affect demographic trends in each species are the same.
Saltmarsh Sparrow,
Photo by Will DeMott
Photo by Will DeMott
Tradeoffs in nest site selection and nest structure across four sympatric species
Avian tidal marsh specialists display an array of nest structure characteristics, including the degree of cover, whether a woven dome covers the nest, how dense the covering surrounding the nest bowl is, how many nest openings there are, etc. They also place their nests in different microsites within marshes.
I am studying the variation in nest site and structure characteristics across Saltmarsh Sparrow, Seaside Sparrow, Willet, and Clapper Rails. The questions I hope to answer: 1. What is the variation in nest structure characteristics within and among species? 2. What nest structure characteristics constrain eggs from flooding out during high tide events? |
Avian eggs float towards the end of incubation. Since tidal marshes regularly flood, tidal marsh bird eggs often flood out of nests during peak high tides. To study whether nest structure traits constrain eggs from flooding out of nests (question #2), I will be artificially flooding inactive nests using mock eggs. |
Behavioral responses to nest flooding
These species exhibit a variety of behaviors when nest flooding events occur. It is unknown whether these behaviors reduce nest failure risk during nest flooding events. Therefore, I seek to answer the following questions:
These species exhibit a variety of behaviors when nest flooding events occur. It is unknown whether these behaviors reduce nest failure risk during nest flooding events. Therefore, I seek to answer the following questions:
- 1. How do tidal marsh bird specialists respond to nest flooding events?
- 2. What factors influence tidal marsh bird flooding behaviors?
- 3. Do these behaviors influence nest fate?
- I am using infrared radiation augmented camera systems to record the responses of chicks and adults to nest flooding.
Tides as a selective force on young sparrow development.
The rate of development in young birds is impacted by the factors that shape their survival. This has mostly been studied in the context of predation. Predation, however, is not always the principle cause of offspring mortality for sparrows that nest exclusively tidal marshes. Flooding from high spring tides may be a strong selective force among tidal marsh sparrows. If acting on development, leg and wing bone and muscles may develop faster in these species than in closely related non-tidal marsh sparrows.
Studying the behaviors each species exhibits in response to nest flooding leads to other questions, such as:
1. Have sparrow species subjected to high amounts of nest flooding evolved the capacity to climb up vegetation at younger ages than non-tidal marsh birds?
2. Are chicks of species that experience higher flooding risk better able to climb at a young age due to earlier allocation of resources to bone ossification and muscle growth?
I am testing these questions by artificially flooding mock nests to determine how high chicks climb within age ranges to avoid drowning due to nest flooding and using chick samples to study morphological characteristics.
Studying the behaviors each species exhibits in response to nest flooding leads to other questions, such as:
1. Have sparrow species subjected to high amounts of nest flooding evolved the capacity to climb up vegetation at younger ages than non-tidal marsh birds?
2. Are chicks of species that experience higher flooding risk better able to climb at a young age due to earlier allocation of resources to bone ossification and muscle growth?
I am testing these questions by artificially flooding mock nests to determine how high chicks climb within age ranges to avoid drowning due to nest flooding and using chick samples to study morphological characteristics.
Thank you to...
Funding
The UConn EEB Demi Fellowship
The UConn EEB Zoology Award courtesy of:
The Francis Rice Trainor
Endowment Fund to the Department of Ecology and Evolutionary Biology and the Connecticut State Museum of
Natural History
The Natural Resources Conservation Academy Research Support Grant
The UConn EEB Zoology Award courtesy of:
The Manter Fund to the Department of Ecology and Evolutionary Biology
and the Connecticut State Museum of Natural History
The UConn EEB Zoology Award courtesy of:
The Francis Rice Trainor Endowment Fund to the Department of Ecology and Evolutionary Biology
and the Connecticut State Museum of Natural History
The UConn EEB Zoology Award courtesy of:
The George Clark, Jr. Fund and the Manter Fund to the Department of Ecology and Evolutionary Biology
and the Connecticut State Museum of Natural History
The Garden Club of America's Coastal Wetlands Scholarship
Site Permission
Hammonasset Beach State Park
Madison Land Conservation Trust
Field Assistants
Sebastian Orue Herrera
Megan Pasternak
Kathy Leone
Will DeMott
Nate Davino
Mackenzie Watkins
Sara Biesemier
Cory Ross
Alexandra Cirata
Laura Jones
Helena Ives
Genevieve Nuttall
Independent Study Students
Aaron Rivera
Marisa Karasik
Max Fenner
Samantha Evans
Isabella Cusano
Valerie Mingrone
Eoin Horning-Kane
Tyrone Tan
Benjamin Ranelli
Kristen Craven
Peter Fahey
Nate Davino
Sara Oraee
Ryan Fiddler
Vigyaan Ramadhin
Rebecca Bullers
Helena Ives