A Northwoods Almanac for March 21 – April 3, 2014
Migratory Birds and Windows Don’t Mix
In a recent analysis of almost two dozen studies and over 92,000 records, federal scientists have found that between 365 and 988 million birds are likely killed in the United States each year as a result of collisions with buildings.
The study (“Bird/building collisions in the United States: Estimates of annual mortality and species vulnerability,” by Scott Loss, et al, in The Condor, February 2014) provides strong evidence that building collisions are second only to feral and free-ranging pet cats (estimated to kill as many as 3 billion birds each year) as the largest source of direct, human-caused mortality for U.S. birds.
The researchers found that roughly 56% of mortality occurred in collisions with low-rises, 44% with residences, and 1% with high-rises. For residences, that translates to between 159 and 378 million birds (median 253 million) that died from window hits.
So, with migration soon to swing into motion, what can each of us do to lessen the number of birds hitting our windows? The most important goal is to make windows – which birds can’t see as people do – visible. Here are some easy tips:
Affix a pattern of tape to windows to help make the glass visible to birds. American Bird Conservancy has created a translucent tape product especially for preventing home window collisions (see www.abcbirdtape.org).
If you don’t want to alter the glass itself, you can stretch lightweight netting or screen over the window. The netting must be several inches in front of the window, so birds don’t hit the glass after hitting the net. Several companies sell screens or other barriers that can be attached with suction cups or eye hooks.
Decals can work if spaced properly. To be effective, decals must be spaced no more than four inches apart horizontally or two inches apart vertically – the shape of the decal apparently has no impact.
For much more information, read the 58-page publication, Bird-friendly Building Design (available at www.collisions.abcbirds.org).
Planting Time Coming – The Importance of Using Native Plants
Since spring is a great time of year to plant perennial trees, shrubs, and herbaceous species, the question is always what to plant. One book with particularly good answers is Douglas Thallamy’s Bringing Nature Home: How You Can Sustain Wildlife with Native Plants.
Thallamy’s thesis is that there are not enough native plants left in the “wild” to support the diversity of wildlife most of us would like to see survive. He contends that we need “reconciliation ecology,” which he defines as the redesign of human habitats to include the lives of other species.
Thallamy, a professional entomologist, argues for the vital role of planting urban/suburban yards and gardens with native plants as the means of saving wildlife. Our native insect fauna cannot, or will not, use alien plants for food; thus insect populations in areas with non-native plants are much smaller than areas with all native species. Insects are very good at converting plant tissues to insect tissue, which is used by higher animals. In fact, a large percentage of the world’s fauna depends entirely on insects to access the energy stored in plants. Birds are a great example – 96%, or nearly all of the terrestrial bird species in North America, rely on protein-rich insects to feed their young.
Some 50,000 alien plants have colonized the US, and the problem is that 90% of insects are specialists – most insects can only eat vegetation from plants with which they share an evolutionary history. Since every plant species has a unique taste, digestibility, and toxicity, native insects typically don’t eat alien plants because they haven’t coevolved to synchronize their life cycle with them. The leaf chemistry of non-native plants is simply too hard to overcome for native insects.
The bottom line? Plant native species if you want to support wildlife.
Numerous other books also provide excellent information on what to plant to attract wildlife. See Birdscaping in the Midwest: A Guide to Gardening with Native Plants to Attract Birds by Mariette Nowak.
Sightings – Eagles working on nest, albino chickadee, northern shrike, three-legged deer
For well over a decade, we’ve watched an eagle nest across the Manitowish River from our house, and on 3/9, we noticed a pair of eagles sitting on the snow-covered nest. Eagles typically are incubating eggs by April 1, with chicks hatching by May 1, the dates varying with weather conditions. Right now, the eagles need a snow shovel to get to the bottom of their nest, but one hopes the snow will melt in time for the female to lay her eggs.
Warren Luy on Squirrel Lake Road has had an albino chickadee visiting his feeder.
On 3/11, Mary and Callie watched a northern shrike that was keeping a close eye on our feeders. The many songbirds that frequent our feeders left immediately and didn’t return for quite a while!
Don Janssen sent us a photo of a three-legged deer eating sunflower seeds from one of his feeders near Squirrel Lake.
And here is an anticipated sighting: In our records over the last 17 years, red-winged blackbirds have returned on average to the Manitowish River on 3/21 – today! We’ll see if the weather breaks enough for a few hardy souls to make the flight north. They have been seen in southern Wisconsin as of 3/12, so it’s certainly possible, but the weather will have the last say.
Tundra Swan Hunt?
The Wisconsin Conservation Congress Annual Spring County Conservation Meeting is set for April 14. Question 36 on the ballot reads: “Are you in favor of the Wisconsin Conservation Congress asking the Wisconsin Legislature to give the WDNR authority to develop a hunting season for tundra swans?”
Their rationale is as follows:
The tundra swan is the most common swan in North American and has very few predators . . . Tundra swans tend to favor larger bodies of water in great numbers as compared to trumpeter swans, which commonly stay in smaller groups and prefer smaller ponds and marshes. The trumpeter swan is well established as a breeding swan in Wisconsin and was removed from the state endangered list in 2009. Studies have shown tundra swan population numbers are currently rising, even with hunting allowed in other states. Each year tens of thousands of tundra swans migrate through Wisconsin with recent peak population counts on the Mississippi River of over 30,000 swans.
This rationale leaves out an important major issue – the close physical similarity between trumpeter and tundra swans. While it’s easy to tell them apart by voice, it’s nearly impossible to tell them apart by sight, even when they’re relatively close.
Thus, shooting trumpeter swans by mistake would likely occur, and that would truly be a shame. Trumpeters were extirpated from Wisconsin in the 1880s and were reintroduced to the state by the DNR beginning in 1987. Over the next quarter century, at a cost of slightly more than $1 million, the birds have come back from zero to between 1,000 and 1,500 in Wisconsin with 214 nesting pairs now gracing 23 counties.
My take is this – in weighing the costs vs. benefits of this proposed hunt, the potential risks of shooting a species that we worked so long and hard to bring back override any potential benefits of a hunt.
Sale of DNR Lands
Since I’m treading, hopefully lightly, some political waters, I may as well jump in a bit further. Under the Authority of s.23.145, of Wisconsin Statutes, Wisconsin Act 20 was introduced in 2013, and directs the Natural Resources Board to make at least 10,000 acres of state land available for sale by June 30, 2017. The law stipulates that land being offered for sale shall be under the jurisdiction of the Department and located outside of project boundaries that were established as of May 1, 2013.
There are certainly some state-owned lands that are isolated and/or some we could do without, but the initial list that has been circulated for review includes 40 acres of land within a State Natural Area boundary – the Ridgeway Pines Relict SNA in Iowa County. The Ridgeway Pine Relict features eight separate pine relicts set among sandstone cliffs, numerous rock outcrops, shallow caves and rock shelters. Pine relicts are southern Wisconsin pine forests that have persisted since the last glacier receded some 12,000 years ago when a cooler climate was favorable for the growth of pine forests. Part of the site is also old field, and the intent of its inclusion was to restore it to mesic prairie and/or oak savanna below the cliffs.
To get more information and form your own opinions, see the initial list put together by the DNR at http://dnr.wi.gov/topic/lands/RealEstate/landsearch.asp.
The Difference Between Localized Weather and Global Climate Data
Continuing the nearly 29-year streak of above-average global monthly temperatures, January came in as the fourth warmest such month on record, according to the National Oceanic and Atmospheric Administration (NOAA). This makes it the warmest January since 2007, and was the 38th-straight January with a global temperature above the 20th-century average.
The global warmth came in stark contrast to the “polar vortex” induced conditions the eastern U.S. and Canada experienced, as well as the cold and stormy conditions in the UK and parts of Russia. Unusually high temperatures elsewhere more than compensated for these cold regions. For example, Southern Hemisphere land temperatures were the highest on record for the month.
In other words, it may have been very cold in the Midwestern and Northeastern U.S., causing all of us to now be genuinely obsessed with the coming of spring, but globally, the planet’s hot streak continues unabated.