During the New Views: Birdlandia exhibition [May 15 – July 16], we’ll explore the subject of birds from different angles.
Vince Cavalieri, a wildlife biologist with the Sleeping Bear Dunes National Lakeshore [SBDNL], has been watching and studying birds since he was 7-years-old. Vince offers an overview of the superior bird watching opportunities in the SBDNL: It’s home to 246 bird species, four of which are threatened or endangered species who reside over 71,199 acres of land, 65 miles of Lake Michigan shoreline, 26 inland lakes, and 12 miles of rivers and streams.
Glen Arbor Arts Center: What kind of bird watching does the SBDNL offer?
Vince Cavalieri: Sleeping Bear Dunes offers a wide variety of habitats in which different bird species can be found while bird watching. These include both inland locations — such as deciduous forests, mixed deciduous and coniferous forests, old field/grassland habitats, interior wetlands, rivers and inland lakes. On the shoreline you can find different species in the dune communities as well as aquatic species in the nearshore habitats in Lake Michigan.
GAAC: Is birding in the SBDNL a four-season activity?
VC: Yes! Birding is a year-round activity, and at a temperate location like Sleeping Bear Dunes the season will profoundly impact what species you might expect. To see the full variety of birds that utilize the park you would have to bird year round!
GAAC: What seasons are busiest for SBDNL’s birds?
VC: Typically the migration seasons of spring and fall will offer the most species of birds as different species that breed farther north or in different habitats will be passing through the park in conjunction with the birds that breed here or live here year round. The busiest time for the birds themselves will generally be late spring and summer when many species are courting, nesting and raising chicks. In general, birds in winter are just trying to get enough food to survive, however a handful of species including owls and some other raptors will begin breeding season even while we would still consider it winter.
GAAC: Are birds busier at certain times of the day?
VC: That depends on the species! Many birds are most active during dawn and dusk periods; these species are known as crepuscular species. They may be active at other times of day as well but their periods of biggest activity will be right around sunrise and sunset. Owls and nightjars — like Whip-poor-wills — are more active at night as are some secretive marsh birds and even a handful of songbirds. While waterfowl and raptors seem to get more active in late morning and into the afternoon.
GAAC: Does SBDNL offer birding programs?
VC: On some of the ranger-led hikes the rangers may include birding as a component.
GAAC: Basic equipment for bird watching?
VC: The beauty of birding is you don’t really need a lot of equipment necessarily; but if you are a person who likes lots of equipment that is certainly plenty to collect! The basic tool of the trade are binoculars. The most typical make for birding is something like an 8 x 40. This means it has 8 power magnification and 40 mm ocular lenses (the bigger lenses farther from your eyes.) Much higher than 8 power and the amount of shake from your hands will be amplified. Forty millimeters for the ocular lenses is a good compromise number, much lower and the binoculars will let in too little light and you will have a dim image of the bird. Much higher and the binoculars will start to get really heavy!
Other important pieces of equipment include a spotting scope, a camera with a telephoto lens if you want to get into photography (though many people now “digiscope” pictures with their cell phones through their spotting scope). For both spotting scopes the prices can vary wildly with the top end binocular and spotting scope option costing thousands of dollars. But much cheaper options are available. In recent years cell phone apps that have built in field guides, all the birds’ songs and other identification guides have become popular, as has the website eBird [https://ebird.org/home] where people go and report their sightings. Most birders also seem to be bibliophiles and hundreds of different book about birds are available!
GAAC: Do you have a favorite field guide?
VC: My favorite field guide for North America is the Sibley Guide to Birds. I feel it has the best plates and the best layout of any current North American field guide. Another popular choice is the National Geographic Guide, which is also quite good and is somewhat more compact and easier to carry into the field (and probably has the best range maps). The venerable Peterson Guide has also been revamped and is still a very good field guide as well.
GAAC: What is the status of the botulism poisoning of birds in the park? What is the vector?
VC: This is a complicated one! To greatly simplify the situation: The problem seems to mainly stem from invasive species. The invasive Zebra and Quagga Mussels are filter feeders and have become so numerous that they filter out so many particulates from the lake that the lake has become clearer. While this may seem like a good thing it actually allows large amounts of a kind of algae called Cladophora to grow in certain parts of the lake. When this Cladophara dies, dense mats of it form on the lake bottom. Inside this mat of dead algae the conditions are perfect for Botulinum bacteria to grow. The bacteria is ingested by micro-organisms which in turn are eaten by fish, especially the invasive Round Goby fish. These fish are then eaten by aquatic birds. The bacteria produce a toxin call botulism, which paralyzes the birds and causes them to drown. This typically is most common in the fall, especially in October and November when a lot of water birds like Common Loons are migrating through the lakes. It can also happen during the summer and has occasion has also lead to the death of endangered Great Lakes piping plovers. Currently researchers are looking into this problem and have discovered a lot about the pathway of the toxin, what parts of the lake bottom the Cladophora seem to grow most frequently in and answers to other important questions.