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Cofrin Center for Biodiversity

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.


1. All About Birds:

2. Manumet Center for Conservation Studies:


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!




Understanding Deep Water

Earth Day is April 22nd and is celebrating its 45th anniversary this year. This year we want to celebrate the month of April by showcasing our commitment to protecting the environmental health of our local communities, Wisconsin and the planet through environmentally based education, research and outreach at UW—Green Bay, the Original EcoU!

The Northeast Wisconsin Groundwater Management Area (GMA) consists of all of Brown County, as well as parts of Outagamie and Calumet Counties. The GMA has an area of around 700 square miles, lies completely within the Great Lakes drainage basin, and is home to more than 350,000 people. Millions of gallons are pumped from the confined deep aquifer in northeastern Wisconsin each day for industrial, commercial, municipal, and residential uses. Some cities now use Lake Michigan surface water for their water supply.  Green Bay switched to surface water in 1957 followed by eight surrounding municipalities  in 2007. These communities still retain many of their high capacity wells to serve as alternative sources in case of emergencies. This switch to surface water has caused a significant rise in groundwater level in the deep aquifer.

Diagram showing how water moves through underground aquifers (from

Diagram showing how water moves through underground aquifers (from

Groundwater in sandstone in the deep aquifer is isolated or confined in the GMA by 3 different overlying stratigraphic rock layers. Some of these rock layers contain groundwater contaminated by bacteria and nitrate or contain faults or fractures that may permit contaminated water to flow into the deeper aquifer.

Amanda Hamby collecting water samples from a home in northeastern Wisconsin.

Amanda Hamby with the equipment she uses to collect water samples from wells.

UW–Green Bay Graduate student Amanda Hamby is working with Associate Professor John Luczaj from the Department of Natural & Applied Sciences to answer the following questions about water in this deep aquifer:

  1. Do regional faults have an effect on water chemistry in the confined deep aquifer in northeastern Wisconsin?
  2. How has water chemistry changed in the Northeast Wisconsin Groundwater Management Area since Green Bay and other municipalities stopped pumping water from the aquifer?

They are collecting water samples from a number of wells in the GMA to assess for alkalinity and a number of ions in the water. Samples will be radio-carbon dated to get an idea of how old the water in the deep aquifer actually is. Amanda is also collecting stable isotopes of oxygen and deuterium that can be used to follow water movement through the atmosphere, surface waters, and into the aquifer. Amanda is using the isotope data she collected in conjunction with GIS mapping to create a natural isotope landscape or “isoscape” of the Northeast GMA deep aquifer, one of very few such maps of deep aquifers.

The results of this project will increase our understanding of how local faults affect groundwater chemistry and water quality in the northeastern Wisconsin. This project will also aid in our understanding of how groundwater level increase in the confined deep aquifer has affected water quality in the Northeast GMA.

Amanda’s research is supported by a grant from the NAS Heirloom Plant Fund at UW–Green Bay.

Mussel Man!

Earth Day is April 22nd and is celebrating its 45th anniversary this year. This year we want to celebrate the month of April by showcasing our commitment to protecting the environmental health of our local communities, Wisconsin and the planet through environmentally based education, research and outreach at UW—Green Bay, the Original EcoU!


Freshwater Mussels from the Oconto River.

Freshwater Mussels from the Oconto River

North America has the highest mussel biodiversity in the world, with over 300 species, but more than 40% of those species are imperiled, especially in the Midwestern states. According to the US Fish and Wildlife Service, no other group of animals in North America is in such grave danger of extinction! The major threats that these species face are siltation, water pollution, damming or conversion of streams, and the presence of invasive mussels (zebra mussels). Wisconsin is home for 51 species of freshwater mussels and 33 of those are considered endangered, threatened or rare enough to be of special concern. Only 18 species currently have healthy populations.

Jesse Weinzinger with fellow UWGB graduate student Chelsea Gunther at the Wisconsin Wetlands Association Meeting.

Jesse Weinzinger with fellow UWGB graduate student Chelsea Gunther at the Wisconsin Wetlands Association Meeting.

UW–Green Bay graduate student Jesse Weinzinger is on a mission to better protect Wisconsin’s freshwater mussels, one of North America’s most diverse and ecologically important aquatic species. Mussels are ecosystems engineers that filter nutrients and particles improving water quality downstream. They also stabilize stream bottoms and provide habitat and food for fish and mammals.

Jesse uses a mask and snorkel to monitor mussel populations.

Jesse uses a mask and snorkel to monitor mussel populations.

The Wisconsin Department of Natural Resources, along with the help of university researchers and citizen scientist volunteers, are surveying mussels in streams to learn more about the lifecycles and population structure of these important animals. However, the current survey protocol is very labor intensive and the state lacks the funds and staff to maintain long term monitoring efforts. Jesse is investigating ways to make the monitoring of Wisconsin’s mussels faster and easier. He is working with the WI DNR to establish a rapid assessment protocol for volunteers of the Mussel Monitoring Program of Wisconsin. The end result will be an efficient, teachable, and easy-to-use protocol that will provide new volunteer opportunities and, if the method is applied successfully, results will provide rigorous quantitative data to inform the DNR as it makes management decisions.

Jesse’s research is partly supported by grants from the Heirloom Plant Sale Fund and from the WI DNR.

How can you help? Become a mussel monitoring volunteer!

Wisconsin Shamrocks!

Did you get a shamrock plant for Saint Patrick’s Day? It was most likely one of a few species in the genus Oxalis. Over 800 different species of Oxalis occur throughout most of the world, especially in Central America and South Africa. Their common name wood sorrel or in Europe wood sour refers to high concentrations of oxalic acid in the leaves and stems. Some are cultivated for their nutritious rhizomes, especially acta (O. tuberosa) in South America. Others like candycane sorrel (O. versicolor) and purple shamrock (O. triangularis), are prized by florists and gardeners because of their showy leaves and flowers and it is likely that you received one of these.

But is Oxalis “the” shamrock? According to Bess Lovejoy writing for, nobody is sure what plant species the stylized 3-leaved shamrock represents. Some, like 19th Century British botanist James Ebenezer Bicheno claimed that wood sorrel (Oxalis acetosella) was the “true” shamrock. Perhaps unconvinced that the British would best know which plant the Irish should call shamrock, Dublin native and amateur botanist Nathaniel Colgan decided to conduct a poll in 1892. He had people from different counties in Ireland send him specimens of shamrocks they had collected. Although there were no single winner based on his results, it seems that the Irish favor a few species of Clovers (Trifolium) especially white clover (Trifolium repens). Botanist E. Charles Nelson, repeated the study in 1988 and found similar results. Although most people selected among several species of clovers, about 5% of participants selected Oxalis as their shamrock.

Oxalis acetosella f. montana

Wisconsin’s Shamrock (Oxalis acetosella f. montana)

White clover is common in our region especially in agricultural and other grassy open fields, however, it is not native and can be invasive, so we are choosing one of our native species of Oxalis, the northern wood sorrel (O. montana or O. acetosella f. montana), as our symbol of the season. The plants are still hunkered down as underground rhizomes, but you will be able to find these forest plants blooming throughout the western Great Lakes region in June. Look for it in boreal and mixed evergreen-deciduous forests or in northern maple beech hardwood forests.

We have several bright yellow flowered Oxalis species in WI which are somewhat associated with disturbed sites, and only two white to pale purple/rose flowered species as in O. acetosella. There is a similar species in southern WI called the violet wood sorrel (O. violacea). The two species are almost perfectly segregated geographically in the state—SW dry and sunny (violacea) versus NE moist to wet and forested (acetosella f. montana).

By Vicki Medland and Gary Fewless

Read more about the history of shamrocks in Smithsonian Magazine online:

Spiders in Search of Beachfront Real Estate!

Dr. Michael Draney (Natural and Applied Sciences) and James Steffen (Chicago Botanic Garden) recently published an article in the journal Great Lakes Entomologist titled “Disjunct Lake Michigan populations of two Atlantic Coast spiders, Disembolus bairdi and Grammonota pallipes (Araneae: Linyphiidae)”.

Steffen and Draney discovered two species of spiders living on the beaches of Lake Michigan that had only ever been found before living near the Atlantic Ocean. Scientists use the word “disjunct” to describe isolated populations like these that are related but widely separated from each other geographically. The discovery that the spiders also live along the shore of Lake Michigan, more than 800 miles inland raises some interesting questions, namely how did these very tiny (less than 2 mm animals) get to the Great Lakes across hundreds of miles of unsuitable habitat?

Populations can become separated from each other when the environment they live in separates into fragments due to geologic or climate events. Continents drift apart, rivers change their course or mountains rise, isolating populations on separate islands of suitable habitat. Populations also become disjunct from each other when species expand their ranges into new territories. This most often happens with species like birds or butterflies that can move long distances, or with species that hitch a ride on floating debris or on (or in) migrating animals.

Beach habitat

Beach habitat.

Can you tell which of the photos is of a beach on Lake Michigan and which is a beach in New Hampshire?

(See the end of this post for the answer.)

While we don’t know how they got so far away from the Atlantic Ocean, the most probable explanation is that individual spiders ballooned inland by releasing long gossamer threads of silk that catch the wind and propel them along like a kite. Ballooning spiders are known to travel even thousands of miles using this technique. Those that were lucky enough to land near the shore of the Great Lakes found themselves in a hospitable and familiar habitat that they could colonize. The spiders do not care where that beach is located as long it provides what they need to survive and reproduce. Suitable habitat probably exists or existed in patches along the St. Lawrence Seaway and the Great Lakes east of Lake Michigan, and spiders may have “island hopped” by ballooning between such somewhat isolated islands of suitable habitat along the way from the Eastern Seaboard to northern Illinois.

Understanding more about disjunct populations like these helps us to understand how specialized species might fare as they become isolated. Under favorable conditions, isolated populations survive, and over time, due to mutation and natural selection, become so genetically different from their far away relatives that the population may evolve into a new species. When conditions are poor and habitats are degraded or lost to development, pollution, or climate change, small isolated populations are more likely to go extinct. By monitoring species like these we can better track the health of the Great Lakes.

Essentially all of the midwest’s plants and animals were absent from the Great Lakes thousands of years ago when the region was glaciated.   Each species has a different history of where it took refuge during those ages, and how it got from there to here.   The intersection of all these unique natural histories contributes to our complex and fascinating regional biodiversity. These Atlantic coast disjuncts are here because of the Great Lakes and the unique coastal habitats they make possible. The present study shows that not just plants (like dwarf lake iris or Pitcher’s thistle) but also animals can be dependent on special Great Lakes coastal habitats. You’ve probably never seen Disembolus bairdi and Grammonota pallipes. Still, these species are two additional (but tiny!) reasons to appreciate our Great Lakes.

The photo on the top was taken by Dr. Robert Howe at White Fish Dunes, WI and the photo on the bottom was taken by Dr. Steve Weeks of dunes in New Hampshire.

New Mushrooms added to our Door County Mushroom Guide


Spinellus fusiger, a mold that infects mushrooms!

Spinellus fusiger, a mold that infects mushrooms!

Late summer and fall have been very wet and that is good for finding more mushrooms. My Door County list has grown to 598 species. The site with the most, 244 species, is Whitefish Dunes State Park. Now Toft Point is in second place with 150. New descriptions of 20 more species found at Toft Point since early September are now on the Cofrin Center for Biodiversity web site, including 68 photos to add for the new species and better pictures for some that are already in the site.

Two species found are also new to Door County. They are Agaricus cretacellus and Gomphidius glutinosus. Fortunately when I found one of these and did not have a camera, my friend Beth Bartoli had hers and was able to get good photographs.

A very different type of fungus was found on a small Mycena species growing on the ground in the woods. It is called the Pin Mold or Bonnet Mould in England. It is parasitic on several species of mushrooms. It was first discovered by a German naturalist in 1818. The Zygospores are produced in black balls at the ends of fine filaments which coat the Mycena mushroom.

Some people despair at the wet soggy autumn, but I rejoice for the welcomed moisture that will aid trees going into the winter season and help mushrooms continue their important work as nature’s recyclers.

Charlotte Lukes

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

Past Peak

In the area around the City of Green Bay many trees have lost all or most of their leaves, especially the commonest and most abundant species such as green ash (Fraxinus pennsylvanica), box elder (Acer negundo), and cottonwood (Populus deltoides). Other species generally leafless now include: white birch (Betula papyrifera), quaking aspen (Populus tremuloides), and wild cherries (Prunus serotina and Prunus virginiana).

Species still holding leaves include the invasive buckthorns (Rhamnus cathartica and Frangula alnus), Norway maple (Acer platanoides) and to a lesser degree silver maple (Acer saccharinum). The oaks also tend to hang onto their leaves, even after they turn brown (see Nov. 4). The photo at left shows still-green leaves of European buckthorn under the mostly bare branches of other species. If you look carefully, you may also notice green leaves still on the branches of a crack willow (Salix fragilis, another alien species) behind the other trees, toward the right side.


A walk in the Cofrin Arboretum

It is still beautiful in the Cofrin Arboretum. Take a walk before the trees are bare!


If birds summering in the Western Great Lakes region have a favorite fruit, it has to be the Juneberry (Amelanchier spp.). Two weeks before the fruit were ripe our resident American Robin would make a daily visit to the trees outside my office, hop from branch to branch, cocking his head to get the best eye-full of berry.  He would sample ones that had already brightened to rosy pink, sometimes dropping the fruit if it was too green. On the day the first fruit ripened, she had the tree to herself for about 3 hours before the first Cedar Waxwings arrived. At the height of the harvest on the single tree, I counted one adult Robin, three juvenile Robins, 8 Cedar Waxwings, a pair of Northern Cardinals, and one shy Grey Catbird that was immediately chased off by the Waxwings.

Cedar Waxwing and American Robin feed on Serviceberries

Cedar Waxwing and American Robin feed on Juneberries

I usually cannot help myself, and sneak out to pick a handful of the fruit for myself. The flavor is reminiscent of blueberries, but has definite plum or dark cherry flavors as well. A serving of juneberries provides 23% of  the recommended amount of iron and are high in potassium, and magnesium, vitamin C, B6, A and E.  Cooking the berries improves the sweetness and flavor of the fruit, so feel free to eat that whole juneberry pie!

There are 20 named species in the genus Amelanchier (Rosaceae). There are almost as many common names to describe these shrubs and small trees  including juneberry,  shadbush, shadwood, shadblow, serviceberry or sarvisberry, wild pear or chuckley pear, sugarplum or wild-plum, and even chuckleberry, currant-tree, or saskatoon.  In the southwest, Amelanchier denticulata is referred to as Membrillo, Membrillito, Madronillo, Cimarron, Tlaxistle, or Tlaxisqui. The common names often vary by location and many relate different phenological events together. Juneberry is obvious, and is most often used for the species that occur in the Midwest where the berries usually ripen in June, (however this year they did not ripen in Green Bay until July 2nd).  Several names refer to the flavor or shape of the fruit including membrillo, which is Spanish for quince, or to location, such as Saskatoon or Cimarron.  Names that include shad are derived from New England and eastern Canada, where the shrubs bloom in early spring at about the same time that Shad (fish in genus Alosa) return to rivers to spawn. Service or “Sarvis” supposedly relates back to the time of itinerant preachers that traveled in New England. The plants bloom in early spring shortly after the trails are clear of snow and the preachers were able to travel to the towns. I could find no source for chuckleberry, but it seems likely a corruption of the older chuckley pear, another name that I could find little history on.

Amelanchiers are important plants for native landscapes. These shrubs provide nectar for early emerging pollinators especially native bees and overwintering butterflies, fruit for birds, and are hosts for the larvae of several species of butterflies. The plants provide four season interest, including beautiful white flowers in early spring, berries in early summer, foliage that that turns to brilliant oranges to deep reds in fall, and beautiful vase shaped silver barked stems in the winter.  There are a variety of forms available to suit most areas from small shrubs to branching specimen tree that can grow to 25 feet in height. The eastern varieties are understory shrubs that are well suited to woodland or shady areas. And if you are lucky and can beat the birds to harvest, the sweet fruit can be used in almost any recipe that calls for blueberries.

Flowers, form, and berries of Amelanchier laevis, a common serviceberry in Wisconsin and the eastern United States. Other species have similar flowers and fruit.

There is at least one species of Amelanchier that is native somewhere on mainland North America and all species are edible, so it should be possible to find a variety that will thrive in your yard. Native varieties should be available at specialty nurseries and many nurseries carry the Apple Serviceberry (Amelanchier X Grandiflora), a hybrid between Amelanchier canadensis and Amelanchier laevis that grows 15 to 25 feet tall and has large showy flowers. There are several named varieties with different growth habits, fall coloration, and disease resistance.  “Autumn Brilliance” is one hybrid variety that is most readily available in the Midwest. All species are edible, although some produce more or larger fruit and new disease resistant horticultural varieties are now available that make growing these plants easy for home gardeners.


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