Notice: register_sidebar was called incorrectly. No id was set in the arguments array for the "Sidebar 1" sidebar. Defaulting to "sidebar-1". Manually set the id to "sidebar-1" to silence this notice and keep existing sidebar content. Please see Debugging in WordPress for more information. (This message was added in version 4.2.0.) in D:\WebSites\blog-dev\wp-includes\functions.php on line 4148

Notice: add_custom_image_header is deprecated since version 3.4.0! Use add_theme_support( 'custom-header', $args ) instead. in D:\WebSites\blog-dev\wp-includes\functions.php on line 3840
skip to content
Cofrin Center for Biodiversity

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.


More information and Recipes

Eleven UW-Green Bay students receive Cofrin Research, Land Trust grants

L to R: Haley Sharpe, Sravani Karnem, Tom Prestby, Brianna Kupsky, Christa Meyer, Mary Quade, Amanda Johnson, and Linda Vang (Not picured: Tim Flood, Jessica Kempke, Amanda Nothem)


Eleven University of Wisconsin-Green Bay students have been selected to receive Cofrin or Land Trust student research grants for the 2013-2014 academic year. These grants provide unique opportunities for students to pursue faculty-guided research that contributes to the conservation and management of natural areas in Northeastern Wisconsin.

The Cofrin grants are available for students conducting research on UW-Green Bay managed natural areas, including the Cofrin Memorial Arboretum, Kingfisher Farm, Peninsula Center Sanctuary, Point au Sable Nature Preserve, Toft Point Natural Area and the Wabikon Forest Dynamics Plot. These grants are made possible through a generous endowment from the family of Dr. David A. Cofrin and the late John Cofrin. The Land Trust Grant is funded by a donation by UW-Green Bay faculty members Michael Draney and Vicki Medland to encourage students to conduct research that contributes to areas managed by recognized land trusts, nonprofit organizations or state or federal agencies.

More information about the Cofrin Grants and UW-Green Bay natural areas is available at Photos and student updates will be available on the Cofrin Center for Biodiversity Facebook page,

Award recipients are as follows:

Land Trust Grant

Tim Flood, Kenosha — An Environmental Science and Policy graduate student, Flood will examine the colonization of plant communities at the Cat Island Chain Restoration Project now under construction in the lower Bay of Green Bay. The island chain is expected to create protected habitats that should support high quality aquatic plants and provide habitat and forage for water birds, fish and other aquatic organisms. The project will provide insight into the current and expected success of the Cat Island Chain Restoration project. Flood will work under the guidance of adjunct faculty member Patrick Robinson.

Cofrin Grants

Amanda Johnson, McFarland — The importance of woodchucks as “ecological engineers” has been suggested for many years, but little documentation is available to support this claim. The UW-Green Bay campus and its Cofrin Arboretum are home to a healthy population of woodchucks, and Johnson, a senior, hopes to learn more about the importance of woodchucks and their burrows to other animals (including red fox, eastern cottontails and other mammals). Under the supervision of Prof. Robert Howe, she will mark and watch burrows with heat-sensitive cameras to capture activity by visitors and residents of old and new woodchuck burrows. The study will provide insights into the importance of woodchuck burrows for maintaining local mammal diversity in semi-natural landscapes like that of the Cofrin Arboretum.

Sravani Karnam, Nairobi, Kenya — Karnam was inspired to study aquatic systems after a presentation by Natural and Applied Sciences seminar speaker Carrie Kissman, an assistant professor of Biology at St. Norbert College who conducts research on trophic cascades in freshwater lakes. Karnam developed a proposal to model trophic dynamics in pond habitats on the Cofrin Arboretum. The primary objective of her study is to understand the trophic organization in the ponds by evaluating the density and composition of phytoplankton and zooplankton at different times of the year. She will use the results to create models of trophic interactions that predict the nutrient conditions and roles of higher-level predators in these systems. Karnam will work under the supervision of Associate Profs. Amy Wolf and Atife Caglar, with assistance from Kissman and Medland.

Jessica Kempke, Green Bay — Graduate student Kempke will be conducting a study of bat migration patterns along the Lake Michigan coast in northeastern Wisconsin using ultrasound recorders or “bat detectors.” These devices record the high-frequency calls of bats, which can be identified in many cases to species. Kempke will compare bat diversity and abundance along the coastline with paired sites 3-5 kilometers inland. Her study will contribute to the knowledge of the distribution of bat species as well as trends in migration and habitat use. Kempke’s project is a collaborative effort with U.S. Fish and Wildlife Service biologists and is part of her graduate research at UW-Green Bay, under the supervision of faculty members Wolf and Howe.

Brianna Kupsky, Green Bay — A UW-Green Bay senior, Kupsky also will conduct research on bats, collecting data at several UW-Green Bay natural areas. This research is a continuation of a study she began last year with the help of a Cofrin Research grant. The purpose of Kupsky’s project will be to develop and implement a systematic monitoring program of migratory and resident bat populations at the UW-Green Bay managed natural areas. This information will continue to create a baseline for future studies and will help verify the composition of resident and migratory bat assemblages at these areas. Kupsky is working under the guidance of Prof. Howe.

Christa Meyer, Medford — Meyer, a senior, already has collected detailed information about a family of red foxes living in the Cofrin Arboretum. Her proposal aims to document the behavior of the adult foxes and their pups during the course of the summer. She also hopes to document the interspecific interactions between the foxes and other animals that occur in the Cofrin Arboretum and UW-Green Bay campus. Christa is working with Howe as an outgrowth of an independent study project during spring 2013.

Amanda Nothem, Campbellsport — Education major Nothem, under the guidance of Associate Prof. Scott Ashmann, will create hands-on K-12 curricula for teacher-guided field trips to UW-Green Bay’s Cofrin Arboretum. The curricula, aimed at educators at different grade levels, will include pre- and post-assessments, handouts, data collection sheets, data analysis sheets and reflection/discussion questions for water and atmospheric testing in the Cofrin Arboretum. Equipment purchased with the grant will be available for teachers to check out from the Education Department.

Tom Prestby, Wauwatosa — Graduate student Prestby will be surveying migratory shorebirds in the coastal zone of lower Green Bay, Lake Michigan. His study will document shorebirds and provide maps of potential shorebird stopover habitat in the lower Green Bay coastal zone. Under the guidance of Howe and Wolf, he will use field data to estimate the extent and variability of habitat for migrating shorebirds in lower Green Bay.

Mary Quade, Green Bay — Mosses are the second most abundant group of land plants on Earth. Senior Mary Quade will be documenting moss abundance and biodiversity at the Wabikon Lake Forest Plot under the guidance of Associate Prof. Wolf. She will document moss community associations and the size and species of trees used by different moss species. Quade’s results will be important for longitudinal studies looking at the effect of climate change on diversity and abundance of mosses, as well as the potential role of mosses as indicators of environmental quality.

Haley Sharpe, Green Bay — An undergraduate, Sharpe will look at the dispersal of tree fungi by woodpeckers. Her project proposes to collect fungal swabs from the beaks of woodpeckers that are captured and banded at the Point au Sable Nature Preserve. Samples from the birds will be grown in the lab and tree fungi identified. This study will help determine the importance of woodpeckers as vectors of fungi between dead and decaying trees. Sharpe will be working under the guidance of faculty members Howe and Wolf.

Linda Vang, Green Bay — Myrmecochory is seed dispersal by ants, and the plants that rely on dispersal by these insects often produce seeds that have an attractive, nutritious structure called an elaiosome. Ants collect the seeds and feed the elaiosomes to their larvae, then discard the seeds outside of their nests. Vang, working with Wolf, will conduct an experimental study to determine the importance of ants in dispersing seeds of wildflowers in the Cofrin Arboretum. Vang, a senior, will identify which ant species disperse seeds and how quickly the seeds are discovered and removed by ants.

Two cases of Insular Gigantism in the Western Great Lakes

Examples of animal gigantism, especially on islands, have long been recognized. Consider, for example, the Madagascar Hissing Cockroach, which is much larger than African mainland roaches. However, it was not until 1964 that a young biologist named J. Bristol Foster published a paper in Nature entitled “Evolution of Mammals on Islands” that explained the phenomena that is now referred to as Island or Insular Gigantism. Foster compared the sizes of island animals and their mainland relatives and surmised that islands contain fewer species than nearby mainland habitats and therefore will have fewer numbers of both predators and competitors. Under such conditions he argued, animals can grow to larger sizes. It is interesting that almost all examples of this evolutionary phenomenon are almost exclusively restricted to islands or other highly isolated habitats. So imagine our surprise when UW—Green Bay botanist and instructor Gary Fewless snapped this photo of an extremely large spider on the UW—Green Bay campus.

UWGB Library expands web use

UWGB Library expands web use

In recent decades other scientists have greatly improved our understanding into why animals on islands can grow so much larger. Large size provides a number of evolutionary advantages to species. Bigger animals can choose from a larger array of food items. Large predators can choose small or large prey. Bigger animals can produce more offspring and provide each with more food and better protect themselves and their offspring.  It is not known whether this is an isolated individual or representative of a new population, perhaps associated with the Cat Island Chain restoration. NAS biology professor and spider expert Michael Draney noted that “Spiders often grow to larger sizes in urban areas thanks to favorable sites for building webs, especially near lights.” However he did add that “This individual is quite a bit larger than the average, though.” Draney, whose specialty are dwarf spiders, shook his head as he considered both the photo and his past advice to area arachnophobes. “Throughout my career,” he said, “I’ve tried to reassure people that spiders in Wisconsin are nothing to worry about. He looked apprehensively out his office window as he added, “All that has changed now.”

It is interesting to note that this is actually the second case of animal gigantism documented in northeastern Wisconsin. Several years ago Fewless, who never leaves his camera far out of reach, also captured the following image of large blue-spotted salamanders feeding on vegetation along the Fox River. When asked about his luck in spotting these unusual animals Fewless suggested that they might not be that out of the norm. “Well”, he said, “there has been an emphasis on growth in this area in recent years. Given our growth in other areas, these animals may not be as large as first thought.  It may just be a matter of perspective.”

Gigantic Salamanders feed along the shore of the Fox River.

Gigantic Salamanders feed along the shore of the Fox River.


2012/2013 Christmas Bird Count

The Christmas Bird Count is 113 years old and is the longest running citizen science survey in the world! Groups of birders get together to count birds over a single 24 hour period between mid December and early January.

This year counts will be held on any day from December 14 to January 5 inclusive. You can find a Christmas Bird Count for your area in Wisconsin at the Wisconsin Society of Ornithology in Wisconsin, there are over 100 counts that take place from mid-December through early January.

The Cofrin Center for Biodiversity will be joining the Dykesville Count on December 16th as this circle includes the Point au Sable Natural Area.  Contact graduate student Tom Prestby at for more information. A Green Bay count that includes the UW—Green Bay campus will occur on December 15th. Contact John Jacobs at for more information.

Horned Lark, photo by T. Prestby

Dykesville birders will be on the lookout for Horned Larks, like this one in the farm fields around Dykesville, WI (photo by Tom Prestby)

The Audubon Society Christmas Bird Count arose out of a 19th century tradition of competitive holiday hunts where groups of hunters competed to see who could kill the greatest number of birds and mammals killed in a single day.  The participants of an 1896 side hunt in a small community in Vermont shot more than 550 birds and mammals. Frank M. Chapman, noted ornithologist and American Museum of Natural History curator, proposed an alternative contest. In the December 1900 issue of his new magazine “Bird Lore” he proposed that people go out and count rather than kill birds and then send their lists back to the magazine.  The first year 25 lists were made by 27 people across the country.

Today, people are participating in the Christmas Bird Count all over the world. Last over 64 million birds were counted in over 2200 areas across 20 countries including Antarctica. That number represents one quarter of all known bird species. Everyone follows the same methodology regardless of country. “Count circles” with a diameter of 15 miles or 24 kilometers are established and at least 10 volunteers count in each circle. Birders divide into small groups and follow assigned routes counting every bird they see along the way. In most count circles individuals are assigned to watch feeders instead of following routes.  A supervisor is designated for each circle and supervises, compiles, and submits data after the count.  The circle that tallied the highest number of species last year was Yanuyaca, Equador, whose team reported 492 species. In the United States the highest count was 244 species reported by Matagorda County-Mad Island Marsh, Texas.

More information:

Visit the National Audobon Society’s website for links to Christmas bird counts throughout North America and the Caribbean

Christmas Bird Count data summaries

Can’t make the Christmas Count this year? Consider participating in the Great Backyard Bird Count Feb. 15-18, 2013.

Origins of the Christmas Bird Count from the North Branch Nature Center, Montpelier VT

A Winter Filled with Finches

Wisconsin birders are looking forward to an excellent finch winter! 

Birds that usually winter in Canada are moving south. These atypical “irruptive migrations” are usually caused by changes in winter food availability and can occur in several northern species especially finches, owls and evening grosbeaks. This year finch species that normally winter in Canada and the northern United States are ranging farther south due to a massive crop failure of fruit and cone bearing trees in Canada.  Birding expert and Ontario resident Ron Pittaway compiles local seed crop and late summer bird observations to create a detailed “Winter Finch Forecast”  available through Ebird every autumn. The Wisconsin Ebird group uses the Pittaway data to create detailed forecasts for our area. Based on the two forecasts we should expect to see Red and White-winged Crossbills, Redpolls, Pine Grosbeaks, Pine Siskins, and Evening Grosbeaks joining resident Goldfinches, House and Purple Finches this winter in northeastern Wisconsin.

Pine Grosbeak photo by  Tom Prestby

Pine Grosbeaks are large finches with heavy black bills and gray sides and red washed black back and reddish pink rump.

Pine Grosbeaks have been steadily moving into the state in small flocks. Look for them on the UW—Green Bay campus feeding on crab apples, especially near the Kress Center. This is a taiga species which is considered an irruptive winter visitor across the Midwest and east.  The last really large widespread movement into Wisconsin was in 1977 and again in 1985. They love to dine on crabapples, high bush cranberries, left over apples in orchards, sumac, mountain ash, and when food supplies are exhausted, the seeds of the box elder ash. Pine Grosbeaks will also switch to backyard feeders when black sunflower seeds are offered, but for now, it is find the fruit trees first!!

Evening Grosbeak photo by Tom Prestby

Evening Grosbeaks are striking birds, identifiable by their large pale bills and black, white, and bright yellow coloration.

Evening Grosbeaks have been on the decline in Wisconsin in recent years and are usually only seen reliably in the far north of the state. Evening Grosbeaks nest as close as Lakewood, Oconto County, annually. However, based on arrival data, the birds being seen now are coming from the northwest. Observations were reported from Duluth as birds rounded Lake Superior. So far this year there are a few reports in Oconto, southern Brown, and Manitowoc counties.  Their preferred seeds are box elder and other maple species. They will also visit platform feeders supplied with black oil sunflower seeds.

Red and White-winged Crossbill species have staged a massive irruption into Wisconsin. Although these birds are unlikely to come to backyard feeders, look for them in conifer swamps and bogs in the far North, the Green Bay area, and in conifer groves along the Lake Michigan Lake shore from Manitowoc down to Chicago. Interestingly, according to Ebird, the Red crossbills arriving in Wisconsin are from western Canada escaping a hemlock seed crop failure in the Pacific Northwest.

Common Redpolls, Pine Siskins, and Goldfinches are common winter residents throughout northeastern Wisconsin and while abundant are not occurring in higher than expected numbers. Purple Finches have apparently moved on and are now below expected numbers. House Finch populations are way up after declining for a number of years. These birds prefer small seeds including birch, alder, willow, tamarack, and weedy field forbs. They will visit backyard nyjer (thistle) and black oil sunflower seed offered in feeders.

Two non-finch species are also irrupting south in response to the seed failures in Canada.

Bohemian Waxwings, while not finches, are another fruit loving bird that is irrupting southward because of the Canadian fruit crop failure and are expected to appear in large numbers in our area this year. In fact a flock of over 250 Bohemian Waxwings seen in Door County was recently reported to Ebird. These birds are voracious fruit feeders so look for them in urban or natural areas with fruit bearing trees like mountain ash, Juniper, and crabapples. These assertive birds will compete with Pine Grosbeaks for access to fruit trees. Bohemian waxwings form pure flocks of their own species or in mixed flocks with Cedar Waxwings.

Bohemian Waxwings are very similar to Cedar Waxwings. Bohemians are larger and have black, yellow, and white wing bars.

Rose-breasted Nuthatches feed on conifer seeds and so are also arriving in high numbers from the same northern regions because of the cone failure. They are often seen at platform feeders eating sunflower seeds and also will feed at suet feeders.

Feeding Finches:

Ebird recommends that people hoping to attract winter finches to their yards put out platform or other large flat surface feeders with black oil sunflower seeds. All finches like small seeded sunflower seeds and some finches like Goldfinches, Redpolls and Siskins also will feed on nyjer in tube or bag feeders. Most finches are attracted to water, so maintaining a heated bird bath or water feature will bring birds to your yard.

It is going to be a very delightful finch winter. 


More Information:

  •  Tom Erdman contributed to the text and Tom Prestby provided photos