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Cofrin Center for Biodiversity

Invasive Plants: Birdsfoot trefoil

Lotus corniculatus

Lotus corniculatus (Birdsfoot Trefoil)

It seems there is an abundance of Lotus corniculatus (Birdsfoot trefoil) along the edges of the paths in the Cofrin Arboretum right now. The name originates from the seed pods that fan out from the stem like a bird foot. The three-lobed trefoil leaves are found in many species in the pea family (Fabaceae). Unfortunately, like so many other wildflowers it is exotic and can become invasive. This perennial plant is native to parts of Europe, Asia, and North Africa, and was probably introduced from Europe as a forage plant for cattle. It is common throughout the western Great Lakes states where the bright yellow flowers are found in  pastures, roadsides, and disturbed riparian areas throughout the summer months.

Birdsfoot trefoil is able to thrive in low nutrient soils because, like other plants in the pea family, its roots contain nodules filled with symbiotic bacteria that can fix nitrogen. The bacteria are able to convert nitrogen in the atmosphere into a chemical form that is easily absorbed by plants. This allows it to easily invade sunny disturbed sites where it will eventually form a deep perennial root mass.

It can form dense low growing mats that shade out native plants and is considered invasive in Wisconsin, Minnesota, Illinois, and 5 other states. Because fire increases seed germination it can be a serious threat to our native prairies. Small plants can be dug up, but all of the roots must be removed to prevent it from resprouting. Heavy infestations are usually treated by repeated mowing or with herbicides.

More Information:

Nicolet National Forest Bird Survey

Join us for the 26th Nicolet National Forest Bird Survey!

This year the NNF Bird Survey will be held on June 8-10, 2012 with headquarters at Trees for Tomorrow  in Eagle River, WI. The Nicolet National Forest Bird Survey is the longest running citizen-science based bird monitoring program in a U.S. national forest.

The Bird Survey takes place each year during the second weekend in June. Everyone with an interest in birds and a desire for adventure is invited to participate in the Bird Survey. Dorm style housing for Friday and Saturday are provided free-of-charge for participants and their families. All meals are provided on Saturday. An early continental breakfast is provided on Sunday.

On Friday eveningvolunteers are assigned to small groups that are led by at least one expert in bird song identification. Other members of the team participate as timekeeper, navigator, or data recorder. So don’t be discouraged from volunteering if you are a novice birder.  Each group selects 6 to 12 sites to survey over the weekend. Each year between 60 and 100 volunteers survey about 150 sites.

Over 60 volunteers joined biodiversity center students and staff and US Forest Service personnel at the 2011 Nicolet National Forest Bird Survey.

The Survey Experience

The Bird Survey begins early Saturday morning when participants gather for coffee and a light breakfast of muffins and fruit at 3:30 am and head out to get to their first site by dawn. Sites can be located along roads, while others require a short hike into the target habitat. Road access points are marked in advance, and directions and gps units are provided along with topographic maps. Once at the site the group counts all birds heard and seen every minute for 10 minutes. They then make a 10 minute audio recording of bird songs at the site. Then it is back in the vehicle and on to the next survey point. Most groups complete their assigned sites by approximately 9:00 am. After they return to camp, groups complete the data forms (to facilitate computerized data entry) and check the forms for accuracy. Lunch is provided and the rest of the day is free for exploring the forest, visiting with friends, and of course taking a nap! Depending on the participants’ interests there might be other afternoon activities like a visit to a nearby wetland to view orchids or dragonflies. On Saturday evening there is a dinner and often a presentation and always contests and prizes for the most interesting and unusual observations.

Volunteers record birds.

Volunteers Mike Grimm, Shirley Griffin, and Bob Ryan record bird songs at an upland hardwood survey point in the Nicolet National Forest.


The quickest way to register is to send an email message to Include the names and ages and sexes of the members in your party and indicate if you will need housing at Trees for Tomorrow and who would like to room together. (Each cabin houses 4 people). You will need to bring your own bedding or sleeping bag and an alarm clock. Also let us know if you will be joining us for lunch and/or dinner on Saturday, so that we can get as accurate a count as possible. Or visit the NNF Bird Survey Website to download an registration form that you can mail in.

Even if you decide to come at the last minute to join us you are welcome. Send us an email or just show up and we will find a place for you!

What to bring besides your personal items.

  • Binoculars!
  • Bird guides
  • Waterproof boots
  • Extra socks
  • Mosquito repellant
  • Field clothes appropriate for the weather
  • Sleeping bag
  • Alarm clock!

Check the website for maps to the camp, schedule, and more information.

History of the Survey

The Nicolet National Forest  encompasses 360,000 hectares of mixed hardwood-conifer forests, lowland swamps, glacial lakes, and wetlands in northeastern Wisconsin. It comprises the eastern portion of the Chequamegon-Nicolet National Forest, with headquarters in Rhinelander and Park Falls, Wisconsin. The Nicolet National Forest Bird Survey began in 1987 in response to the lack of quantitative information about the breeding birds in northern Wisconsin.

Wildlife Biologist Gary Zimmer, who helped to organize the first Nicolet National Forest Bird Survey in 1986, speaks to the volunteers at the 2011 Survey.

Following publication of the 1986 Land and Resource Management Plan for the Nicolet National Forest, members of the Conservation Committee of the Northeastern Wisconsin Audubon Society wanted to provide a better foundation for assessing the impacts of forest management on bird populations. A proposal was submitted to Forest Service Biologist Tony Rinaldi, who worked with the Audubon Society members to organize the first Nicolet National Forest Bird Survey at the Boulder Lake Campground. The survey now alternates, surveying points in the northern or southern sections of the forest each year.

Over  400 volunteers, including many of Wisconsin’s premier birders, including Sam Robbins, Noel Cutright, Bettie Harriman, Tom Schultz, Jim, Jeff, and Scott Baughman, Andy Paulios, Laura Erickson, John Feith, and others, have joined biologists from the US Forest Service and the University of Wisconsin Green Bay over the years to conduct the annual survey. Biologists and volunteers have now compiled more than 40,000 records of birds at 522 points, most of which have been sampled every other year since 1987 or 1988. This data has been used by many researchers and has contributed to several theses and scientific publications.  Most importantly, the effort of our outstanding and dedicated citizen scientists has resulted in improved management of our northern forests and a better understanding of the ecology of forest birds.

Lower Fox River Watershed Monitoring Program

Recently the University of Wisconsin-Green Bay held the ninth annual Watershed Symposium for The Lower Fox River Watershed Monitoring Program. The LFRWMP partnered with many programs to aid in their research and give the students an opportunity to learn more about watershed monitoring. These program partners were Appleton East High School, Appleton North High School, Ashwaubenon High School, Boys & Girls Club of Green Bay, Green Bay East High School, Green Bay Preble High School, Green Bay Southwest High School, Luxemburg-Casco High School, Oneida Nation High School, Oshkosh North High School, Pulaski High School, and West DePere High School.



The LFRWMP is a continuing program that provides high-quality data which is used for making decisions about improving water quality and foster habitat restoration within the Fox River Basin. The Lower Fox River Watershed Monitoring Program has four main goals

  1. Strengthen student and teacher knowledge and understanding of land use impacts on water quality and stream ecosystems
  2. Enhance teacher capacity to teach watershed science by providing hands-on training in water quality and biological indicator monitoring techniques and data interpretation
  3. Develop a long-term watershed integrity database that helps users understand changes over time and contributes to improved watershed management strategies
  4. Provide ongoing opportunities for high school students and teachers to engage in hands-on science and to interact with other students, university scientists, resource managers and community professionals


To read more about the LFRWMP go to



Students from the program partners are allowed the opportunity for hands-on field work sampling and their school research posters, presentations, and videos can be found at


The symposium and Lower Fox River Watershed Monitoring Program are supported by a gift from Arjo Wiggins Appleton Ltd.




Everyone has noticed how strange our spring weather has been this year. One thing you might be wondering is why this occurred, or how this weather affects the natural world. The study of the timing of natural events is called phenology. There are three main factors that affect phenology 1) sunlight 2) temperature and 3) precipitation. Some examples of phenology include when migrating birds return, when plants first flower, and when lakes freeze and reopen. It is important to keep phenological records. By keeping records it allows us to look at the changes over the years at different geographic regions. This also helps us understand interactions between organisms and their environment and the effects of climate change. The Cofrin Arboretum Center for Biodiversity keeps records of important natural events in the western Great Lakes region during all months of the year. These records can be accessed at The Wisconsin State Climatology Office also holds an impressive database which you can access at

Why is phenology so important? Over the years we observe that phenological events vary. Ecosystems are able to recover from variation between years but when these changes happen consistently over a long period, the timing of events (flowering, leafing, migration, and insect emergence) can impact how plants and animals thrive in their environments.  The success and survival of an ecosystem depend on the timing of phenological events. For example, if the timing of emergence of leaves changes it can result in fewer seeds/insects which would impact animals that depend on those seeds/insects for food. Consider the difference in spring vegetation in the Cofrin Arboretum between May 4th of  2010 and 2011. Early leaf-out can result in a longer growing season and better habitat as long as a late freeze does not kill tender vegetation or developing flowers or fruits.

Prairie Pond in the Cofrin Arboretum shown on May 4th in 2010 (left) and 2011 (right).

 On the Wiscoonsin Statewide Monthly Temperature for the last 12 months graph it is shown that the monthly average temperature for this year is obviously higher when compared to the normal monthly temperature.

Figure courtesy of the Wisconsin State Climatology Office website.

 This temperature increase leads to sooner blooming of flowers and plants as well as earlier date arrivals for some migratory birds. This year the early migratory birds have to fight a little harder to survive. On the cold days when there aren’t any insects small birds have a more difficult time staying warm and full because they have nothing to eat. If they would have waited to return at their normal migration date they may not have this type of problem. Everything is inter-linked in nature and the weather plays a key role in determining what survives and what doesn’t. It will be exciting to watch this interesting weather continue throughout the year.

Spring Prairie Chicken Trip

Spring brings many new things with it as it approaches (rather early this year I might add). One of the most interesting and entertaining things I have experienced is Prairie Chicken Booming. I had no idea what to expect on this trip, but I was in for a real treat.

On the trip, the group hid from the birds in plywood blinds like the one shown above.


 Prairie Chickens are one of four native grouse (Ruffed Grouse, Sharp-Tailed Grouse, and Spruce Grouse). Prairie Chickens prefer grasslands for nesting, brood-rearing, roosting, feeding, and loafing. They also prefer wide horizons which allow them to see and be seen for great distances.


A male Prairie Chicken inflates the orange air sacs located on the side of their neck as he displays to a female.


What is Prairie Chicken Booming? It is the courting of a female Prairie Chicken by multiple anxious male suitors. In the spring, males (cocks) gather on booming grounds or leks. Males battle each other for the small territories (50 feet in diameter) with displays, postures, and physical combat. Cocks occupy the same territories every morning during the mating season. At the end of these battles some of the males end up pretty battered and bloodied. Besides fighting for the ladies’ attention, cocks advertise with foot stomp dances, displaying feathers, orange eyebrows and air sacs, snapping tail feathers, and “booming” which can be heard greater than one mile away on still mornings. Booming is a three note call that is enhanced by their inflated air sacs. When females (hens) are present, cocks intensity their displays by adding a “whoop” to their three note boom. As I sat out in the brisk morning air I compared the Prairie Chickens to cartoon characters with their eccentric jumping and curious sounds.


Prairie Chickens have a pretty interesting back-story as well. In the early 1900’s Prairie Chickens flourished and were hunted until 1955. Grassland habitat began to disappear due to farming, tree planting, and natural succession and in turn the Prairie Chicken numbers plunged. The best remaining populations were in central Wisconsin and initial land was acquired on the Buena Vista Marsh in 1954.  Drs. Frederick and Frances Hamerstrom were instrumental when it came to the preservation of this species. They both studied under Aldo Leopold who was an avid environmentalist and brilliant professor from the University of Wisconsin. The Hamerstroms revolutionized wildlife study with their work on Prairie Chickens. Through their research and commitment they preserved the existence of Prairie Chickens in Wisconsin. It is because of them that we still have this unique bird in our state.



Assessing Coastal Hazards in Great Lakes Communities

You know those scenes in movies where the main character is standing on the edge of a cliff and all of the sudden the ground falls out beneath him and he drops into the water? In Great Lakes communities, that is an actual concern for some people.

There has been an increasing demand for a new standard of care to be upheld in the Great Lakes. People demanded that we not just minimize harm but also rehabilitate the Great Lakes. In February 2009 President Obama proposed a $475 million Great Lakes Restoration Initiative Action Plan. The Great Lakes Restoration is now a National Priority.

There are five significant ecosystem problems in the Great Lakes.

  • Toxic Substances and Areas of Concern (e.g. pollution prevention and clean up)
  • Invasive Species
  • Nearshore Health and Nonpoint Source Pollution (e.g. reduce polluted runoff from urban, suburban, and agricultural sources)
  • Habitat and Wildlife Protection and Restoration
  • Accountability, Education, Monitoring, Evaluation, Communication, and Partnerships


The green color of the bay comes from chlorophyll present in algae.

Where does the Biodiversity Center fit into all of this? The Center is hosting a workshop that will be held at UWGB on June 19, 2012. This workshop focuses on developing online tools to help local decision-makers address hazard related threats and effects of climate change on Great Lakes communities. For example, if a company wanted to build on a bluff near Lake Michigan they would have to talk to a zoning director about how close to the edge of the bluff they can build. The zoning director could use these online tools to figure out how far away from the edge the building has to be so it won’t be at risk of falling into the water someday due to bluff erosion. The goal of this project is for coastal communities to have a better understanding of how they may be impacted by the hazards of a changing climate, and to provide new tools and information for developing adaptive plans.

At this workshop, decision makers will have the opportunity to interact with the online tools. The tools incorporate geospatial data, science-based information, and visualizations. The goal is for decisions-makers to understand and document the effects of “proposed projects” and what liabilities those projects may create for the community. At the workshop, the instructor will propose a project and the users can use the tools to consider if the project will:

  • Accelerate/amplify existing hazards (e.g. erosion and flooding)
  • Increase infrastructure costs and liabilities related to flooding and shoreline protection
  • Worsen resource management challenges associated with water quality, habitat conservation, and the public trust doctrine
  • Decrease the economic, cultural, physical, and ecological resilience of natural and built coastal environments

After the workshop, the users will give their feedback based on their experience with the online program. This feedback is vital in determining how beneficial these online tools will be for local officials in their decision making tasks.

There are four main categories for the online tools.

  • Hazards Management and Planning: this section of the online tools is based on demographic data, land use and parcel data, hazard and flood maps, and climatology data (e.g. extreme temperatures, precipitation change, and flood events).
  • Coastal Erosion and Bluff Recession Prediction: the section demonstrates the connections between weather and climate conditions, coastal recession, bluff retreat hazards, and shoreline management strategies.
  • Coastal Infrastructure Planning: the section focuses on coastal structures including their maintenance costs, effectiveness and regional impacts (e.g. hardened shorelines, recreational and commercial use).
  • Habitat Conservation and Restoration Planning: this section focuses on protecting the region’s key ecosystem resources, especially maintaining the protective and beneficial functions of natural floodplains.

The National Oceanic and Atmospheric Administration (NOAA) Coastal Services Center and Association of State Floodplain Managers are key partners for this project.

The Big Day – Bird Survey April 27, 2012

The Big Day Bird Survey final total was 56 different species found around the UWGB campus and arboretum area, a fantastic number! Dr. Howe’s Spring Ornithology class went out at 7:00am to start their share of searching in the morning. The count continued until midnight. The 50th bird species seen was a Blue-gray Gnatcatcher, the first one of the year at UWGB!

April 27, 2012 Big Day Bird Survey


  1. American Crow
  2. Killdeer
  3. Herring Gull
  4. Ring-billed Gull
  5. Double-crested Cormorant
  6. Lesser Scaup
  7. American White Pelican
  8. Mallard
  9. Mourning Dove
  10. Common Goldeneye
  11. Red-breasted Merganser
  12. Northern Cardinal
  13. Redhead
  14. Greater Scaup
  15. American Black Duck
  16. American Wigeon
  17. Gadwall
  18. Purple Martin
  19. Tree Swallow
  20. Song Sparrow
  21. Canada Goose
  22. American Robin
  23. Blue Jay
  24. White-throated Sparrow
  25. Wild TurkeySearching for the Blue-gray Gnatcatcher!
  26. Brown-headed Cowbird
  27. Red-winged Blackbird
  28. Black-capped Chickadee
  29. European Starling
  30. Common Grackle
  31. Bald Eagle
  32. Ruddy Duck
  33. Great Egret
  34. House Wren
  35. American Goldfinch
  36. Chipping Sparrow
  37. Eastern Bluebird
  38. Barn Swallow
  39. Lesser Yellowlegs
  40. Northern Rough-winged Swallow
  41. Cooper’s Hawk
  42. House Sparrow
  43. Cliff Swallow
  44. Yellow-bellied Sapsucker
  45. White-breasted Nuthatch
  46. Downy Woodpecker
  47. Red-bellied Woodpecker
  48. Northern Flicker
  49. Yellow-rumped Warbler
  50. Blue-gray Gnatcatcher
  51. Red-tailed Hawk
  52. House Finch
  53. Rock Pigeon
  54. Sandhill Crane
  55. Great Horned Owl
  56. Turkey Vulture

National Estuarine Research Reserve Climate Sensitivity Analysis Project

Patrick Robinson

By Chelsea Gunther


Patrick Robinson, an adjunct faculty member and Cofrin Center for Biodiversity affiliate, is working on a project examining the effects of climate change, both socially and ecologically. He is working on this project along with other researchers from the University of Wisconsin-Madison, University of Wisconsin-Extension, and National Oceanic and Atmospheric Administration (NOAA) Cooperative Oxford Laboratory in Maryland.

So what is NERRS? It is the National Estuarine Research Reserve System. This system contains 28 diversely located reserves. These reserves are being exposed to several human-related (anthropogenic) and climate-related stressors. The goal of this project is to understand how climate change impacts coastal areas and categorize each reserve based on the results of the anthropogenic and climate impacts. The team plans to present the project results in the fall of 2012.

Whose idea was it? NOAA’s Climate Program Office is developing a partnership with the Office of Ocean and Coastal Resource Management. It is their goal to understand how climate change impacts coastal areas.

How do they plan on doing this? The team is taking a three step approach. First they analyze and synthesize key data describing physical, ecological, and socio-demographic characteristics in these areas. Second, they isolate the main anthropogenic and climate stressors impacting the reserves. Examples of anthropogenic stressors are nutrient enrichment, sedimentation, hypoxia, and physical disturbance including water diversions. Examples of climatic stressors are sea level rise, precipitation frequency and intensity, and drought. Third, from the data they have gathered they will categorize each reserve based on their results to those stressors. Assigning each reserve to different categories allows the research team to better assess the impacts from humans as well as climate on these coastal ecosystems.

Why are they doing this? NOAA hopes to continue further investment in this program and share the information learned with similar projects.  The research will help prioritize future environment vulnerability assessments and planning efforts.

The Red River Breaks are a part of the St. Louis River Freshwater Estuary and Lake Superior National Estuarine Research Reserve.

A new reserve, the Lake Superior NERR, was designated in Wisconsin in 2010 (see Patrick, along with many others, worked for over four years on the designation process for the reserve. The Lake Superior NERR represents only the second reserve on the Great Lakes, with the other being in Ohio on Lake Erie. 

Holiday Cluster Flies

Last week I was at a concert where two large fresh-cut trees had just been brought in. I noticed several insects lazily flying about the auditorium and when one landed nearby we recognized it as a cluster fly.  I knew that cluster flies overwinter in attics and walls like Asian Ladybugs, but I wondered if they could also overwintering in Christmas trees. Last year I had seen these same insects shortly after we brought in a fresh-cut Christmas tree as well. Did they come in on the trees?

Cluster fly larvae are non-native imports from Europe.  They are not considered invasive in northeastern Wisconsin because they are parasites on earthworms, which are also not native to our area.  In the autumn adult flies search out protected over-wintering sites. In the wild these would be under bark or in dense vegetation or other crevices in rocky piles or cliff faces. Of course buildings mimic cliff faces to these insects, and the flies will cluster under siding and in walls or attics. Christmas tree farms are likely to provide good overwintering sites if there are brush piles or dead trees or sheds nearby. But it isn’t too likely they could use living Christmas trees successfully because there are few good places for them to hide.

I spoke with UW Madison entomologist Phil Pellitteri who agreed the flies are unlikely to find good winter protection in Christmas trees and suggested that the flies were probably in the building and were roused by warm outside temperatures. Wherever they came from they are slow and easy enough to catch. Unlike other “house” flies, cluster flies do not feed in our houses and are unlikely to spread disease.

Cluster Fly (Phormia rudis). Photo by Gary Fewless.

Cluster Fly (Phormia rudis). Photo by Gary Fewless.

Are cluster flies a pest? That probably depends on how many there are in one place. They can sometimes accumulate inside walls and attics in large numbers. When temperatures rise on warm days some flies become active and make their way into living spaces. Once inside, they are not easily controlled by pesticides. Experts at the Entomology department at Penn State  and UW Extension suggest killing flies trapped in walls or attics might makes matters worse because the dead flies will attract other more onerous pests like carpet beetles that would  invade closets and rugs looking for wool and furs after they devour the flies.

Real Christmas trees are clearly the better choice for the environment when compared with artificial trees. They sequester carbon, produce less pollution and waste when recycled, and tree farms provide habitat that helps to preserve local biodiversity. Sometimes people are worried about that biodiversity, especially insects or spiders, coming inside with their trees. The best way to remove any stowaways is to give the tree a good shake before bringing it in the house. Fresh Christmas trees should never be sprayed with chemical pesticides, which are flammable and environmentally unfriendly. And of course sprays would ruin that wonderful fresh conifer scent.


Phillip Pellitteri, University of Wisconsin Diagnostic Laboratory:

Insect Advice from Pennsylvania State Extension:

University of Wisconsin Extension News: “Homeowners find fall insects unwelcome guests.”

The Nature Conservancy “Real versus fake Christmas trees”

Point au Sable Bird Survey: November 3, 2011

Today, Marty Jacobson, Josh Martinez and I conducted bird point counts at Point Sable for sites 3, 5 and 9. Soon after arriving, we had nice looks at a lone Pine Siskin (Spinus pinus) from point 3. When we reached the end of the point, we could see many distant ducks but there was also a Common Loon (Gavia immer) fairly close in (see photo below). Also at the point, we had 9 swans fly over. They were either Tundra (Cygnus columbianus) or Trumpeter (Cygnus buccinators), but we were not sure which. Several other interesting flyovers included 10 Bonaparte’s Gull (Chroicocephalus philadelphia) at point 5, 4 Horned Lark (Eremophila alpestris) from point 6 and a Rusty Blackbird at point 3. Migrant passerines included Fox Sparrow (Passerella iliaca) and Hermit Thrush (Catharus guttatus). Marty asked if Josh or I ever see owls at Point Sable and almost on cue we found two Great Horned Owls (Bubo virginianus). One of the last birds we saw was a Belted Kingfisher (Megaceryle alcyon) fishing in Wequiock Creek.


Common Loon

Common Loon at Point Sable. 3 November, 2011.