Snapshots that help conserve shorebirds in decline

Scientists collect a snapshot of a bird’s life when they capture, band, and release it. Each coded band and any data collected at the same time like date, location, sex, age etc. are recorded in a database that can be shared by scientists around the world. When the same bird is seen somewhere else, that observation location provides another snapshot that is added to the database, helping scientists to reconstruct the movements of individual birds. This continuously growing database makes it possible to study dispersal and migration, behavior and social structure, life-span and survival rate, reproductive success and population growth.

Environmental Science & Policy Master’s candidate Tom Prestby is observing shorebirds migrating along the lower Bay of Green Bay (Brown County, Wisconsin, USA) in order to provide much needed information about the importance of near shore habitat for numerous species of conservation concern including three species in high peril and 12 in high continental concern.

Semipamated Sandpiper photo by Tom Prestby
Semipalmated Sandpipers on the shore of the Bay of Green Bay.

He photographed the Semipalmated Sandpiper shown here in late May 2015 at his research site in Green Bay. The code on the blue band on the bird’s leg allowed him to discover that it was banded on January 14, 2014 in Maranhao, Brazil, and so had traveled nearly 2000 miles to get to Green Bay. Semipalmated Sandpipers, so-named because their toes are webbed for only part of their length, breed on open tundra, so it’s journey is only a little more than half finished. It still must travel another 1200 miles or more to northern Canada and Alaska to breed this summer, resting at along mudflats, sandy beaches, shores of lakes and ponds, and wet meadows. These birds make that incredible 3000 mile journey in only about two months time and rely mostly on stored fat reserves to power them through migration.  Summer is short in the arctic, so after they breed they begin their fall passage in July at a more leisurely pace and typically arrive back in their South American wintering grounds by mid-October.[1]

Unfortunately, this species is on the 2014 State of the Birds Watch List, which lists species most in danger of extinction without significant conservation action. Even though populations appear to be stable at some arctic breeding grounds in Alaska, surveys by researchers in Canada and the United States indicate that the numbers of birds reaching South America wintering grounds have declined by 80% over the last 20 years. Canadian scientist Stephen Brown who has been tracking the birds as they arrive on Coats Island in the far north of Hudson’s Bay explains, “We need to understand the migratory pathways of the species in order to know where the decline is occurring, and what can be done to reverse it.”[2]

Prestby’s observation is helping other scientists to do just that. He is continuing to monitor shorebirds at his research sites including the recently restored Cat Island Chain in person and through the use of remote cameras. He is enthusiastic about his graduate experience. “It is fascinating to be able to look into the life of one of these birds and very satisfying to contribute to a great database!” His master’s research will provide important information about shorebird migration and use of wetlands encircling the bay of Green Bay that will help scientists to better understand and conserve these trans-American travelers.

References

1. All About Birds: http://www.allaboutbirds.org/guide/Semipalmated_Sandpiper/id

2. Manumet Center for Conservation Studies:  https://www.manomet.org/newsletter/first-ever-geolocator-results-semipalmated-sandpiper-show-remarkable-year-long-odyssey

 

Considering a career in Environmental Science? Learn more educational opportunities for undergraduate and graduate students at the University of Wisconsin–Green Bay, the Original #EcoU!

 

 

 

Bird Banding at Point au Sable

Almost 80% of songbirds that nest in Wisconsin are migratory, many traveling vast distances every spring and fall. Songbirds typically migrate at night and seek out patches of natural habitat at daybreak where they can rest. These areas must provide shelter from storms and predators, as well as provide high quality food resources so the birds can refuel for the next leg of their journey.  Unfortunately, stopover habitats are becoming scarcer as natural habitat is converted for human use and landscapes become more fragmented.

UW--Green Bay graduate student Stephanie Beilke measures a bird while undergraduate Kirsten Gullett records data.
UW–Green Bay graduate student Stephanie Beilke measures a bird while undergraduate Kirsten Gullett records data.

Stopover habitats are a critical resource for these birds, but the ecology of birds during stopover periods is not well understood. And because increasingly large numbers of birds congregate in these fragmented habitats, ecological interactions can be intense. This may because there are many species interacting under highly variable environmental conditions. Graduate student Stephanie Beilke is banding birds to learn more about how migratory birds are affected by the type of stopover habitats they choose.  Her research on migratory bird assemblages will provide insights into the resource demands and evolutionary history of migratory birds and will ultimately provide a better understanding of stopover site ecology and help guide the conservation and protection of Great Lakes coastal habitats for migratory birds.

Point au Sable offers a perfect opportunity to learn more about stopover ecology. It is a mosaic of different natural habitats including lowland and upland forest, wetlands, and Great Lakes beach.  Since the late 1990s, migrating passerines have been studied at Point au Sable Natural Area, a peninsula that juts out into the lower Green Bay, just north of the University of Wisconsin-Green Bay campus.  Through the years, Point au Sable has experienced many ecosystem changes including invading exotic vegetation, declining water-levels in the Bay of Green Bay, and ongoing habitat management and restoration. Despite these changes, point counts and mist-netting operations conducted by UW – Green Bay researchers have shown that large concentrations of avian migrants use Point au Sable during both spring and fall migration

This fall Stephanie and her group of volunteers set up nearly invisible finely-meshed mist nets in openings where birds are likely to fly through. Birds fly into the nets and become entangled. Trained technicians collect the birds, and then take measurements and either read the existing band or place a new a U.S. Geological Survey aluminum numbered band on the bird’s leg. Volunteers help to set up and take down the nets, alert the technicians to new arrivals, and help to record data collected.  In this study netted birds will be weighed and scored for visible chest fat.  Different length and width measurements are also collected.  Technicians work quickly and carefully to limit the amount of stress endured by the birds.

They banded birds on 25 different days at two locations at Point au Sable Natural Area. Six mist nets were set up in either coastal shrub or in upland forest. The average capture rate was 40 birds per net, but one net in the coastal area caught 79 new birds as well as 3 recaptured birds. Forty-seven different species were banded, including 100 Tennessee Warblers. They also captured large numbers of White-throated Sparrows, American Robins, Hermit Thrushes and Golden-crowned Kinglets.

Some of the species they caught were “firsts” for the project, meaning they had never been captured before, including Black-billed Cuckoo, Blue-headed Vireo, Purple Finch, and Winter Wren. The crew also banded one Yellow-bellied Flycatcher on October 12, which, according to the Wisconsin Society for Ornithology, makes it a record late observation for the state. Most Yellow-bellied Flycatchers have migrated south by the end of September.

Stephanie will be banding again Spring 2014, stay tuned to the blog or like us on Facebook to find out how to volunteer.

Some of the birds captured in Autumn 2013

Brown, Kewaunee, Shawano, and Oconto Bird Surveys: May 26 to June 24, 2010 by Erin Gnass

As I mentioned in one recent blog posting entitled “May 26, 2010 by Erin Gnass,” I performed bird surveys for the greater part of the month of June for my thesis project—the index of ecological condition model, as applied to northern hardwood forests of Wisconsin. In order to most appropriately create this model, I surveyed additional hardwood forested sites considered to be of poorer forest condition so as to sample across a wide range of environmental condition. This enables the model to be more accurate and effective at calculating forest condition. Therefore, I went in search of hardwood forest sites on both public and private lands near and within heavily managed, fragmented, and human-disturbed or developed areas. Within Brown, Kewaunee, Shawano, and Oconto counties here in east-central Wisconsin, I found 27 sites that I surveyed, with the much-appreciated assistance of Joan Berkopec (the same wonderful volunteer who helped with the Wild Rivers Legacy Forest surveys and the Nicolet National Forest Bird Survey that I described in the two previous posts).

From May 26 until June 24, I observed 49 total species at these 27 additional sites, including the following species of interest:

Seven warblers:  Chestnut-sided, Common Yellowthroat, Mourning, Northern Waterthrush, Ovenbird (in moderate numbers), Pine, and Yellow Warblers

Seven woodpeckers:  Downy, Hairy, Northern Flicker, Pileated, Red-bellied, Red-headed, and Yellow-bellied Sapsucker Woodpeckers

Four flycatchers:  Eastern Phoebe, Eastern Wood-Pewee (in moderate numbers), Great Crested (in moderate numbers), and Least Flycatchers

Three thrushes:  American Robin (in moderate numbers), Veery, and Wood Thurshes

And one vireo:  Red-eyed Vireos (in large numbers)

Please feel free to look at the photographs that I took shown below:

Hardwood forest in Brown County
WI DNR sugar maple forest plot in Shawano County
While scouting out potential survey sites in Brown County, I heard then observed this spectacular Mourning Warbler pictured here
One of two Red-headed Woodpeckers that I found nesting along the pond at the Brown County Pet Exercise Park, which is full of sugar maple hardwoods
Red-headed Woodpecker
One of the two Red-headed Woodpeckers at their nesting cavity site

Thank you to professional photojournalist, Scott Giese, my boyfriend, for taking these additional photographs of me while I completed a bird survey in Brown County:

Me, Erin Gnass, obtaining a GPS coordinate at a bird survey site in Brown County
Me, Erin Gnass, recording data for a bird survey in Brown County
Me, Erin Gnass, trying to obtain a visual observation of a bird during a bird survey in Brown County

Nature Conservancy Bird Survey: May 26, 2010 by Erin Gnass

Because I have been in the process of preparing for my graduate thesis field work this summer, I have not had a chance to perform any additional bird surveys at Point au Sable. I will be heading to the northern hardwood forests of Wisconsin on Saturday to assist in performing over two-hundred bird surveys with the Nature Conservancy (TNC) for my thesis research. For my thesis project, I am developing a probability-based ecological indicator model for over 65,000 acres of forested land that is managed by TNC, the state of Wisconsin, and timber investment management organizations in the Wild Rivers Legacy Forest (WRLF). Based on an environmental gradient (ranging from degraded to pristine forest conditions), this ecological indicator will utilize the presence and absence of assemblages of bird species to indicate the ecological condition and conservation health of the forested lands of the WRLF. This indication of ecological condition will provide timber managers within the WRLF assistance in monitoring and managing these forests in a sustainable manner for both humans and wildlife.

In preparation for the model, TNC surveyed sites in the northern hardwoods of Wisconsin for forest bird species in the summer of 2009. This summer, I will be fortunate enough to join the team of ornithologists and survey the same sites as well as others, starting this Sunday. Additionally, in order to survey sites across the entire environmental gradient, my graduate advisor, Dr. Bob Howe, and I are surveying additional areas of varying forest condition including fragmented, isolated, and/or human-used areas in the Brown County area in order to most appropriately create this ecological indicator model. Therefore, we started these additional surveys yesterday morning in areas including and surrounding Brown County. All of this data will then ultimately contribute towards the conservation, protection, and sustainable use of northern Wisconsin hardwood forests.

Yesterday, we went to the managed forests of the Reforestation Camp in Suamico, Wisconsin and found 31 total bird species, including many species of particular interest:  Mourning Warbler, Northern Waterthrush, Pileated Woodpecker, Scarlet Tanager, Veery, and Yellow-bellied Sapsucker. We also found American Crow, American Goldfinch, American Robin, Black-capped Chickadee, Blue-gray Gnatcatcher, Brown-headed Cowbird, Blue Jay, Canada Goose, Common Yellowthroat Warbler, Downy Woodpecker, Eastern Wood-Pewee, Great Crested Flycatcher, Gray Catbird, Hairy Woodpecker, House Wren, Indigo Bunting, Mourning Dove, Northern Cardinal, Ovenbird, Red-bellied Woodpecker, Red-eyed Vireo, Red-winged Blackbird, Sandhill Crane, White-breasted Nuthatch, and Wild Turkey.

Although I will be in northern Wisconsin for the next few weeks, I will provide a few reports about my thesis work and  the annual Nicolet National Forest Bird Survey (June 11-13) when I return to Green Bay. Then, once I am back from field work, I will survey Point au Sable again and provide weekly updates. So please stay tuned!