The Bird Migration Continues at a Rapid Pace
Wetland Birds Are Arriving at White Memorial
by Paul Fusco
Many different types of birds can be found in wetlands, but the ones that we refer to as wetland birds generally fall into the heron and rail families. Virtually all of them spend the winter well-south of Connecticut since they don't have any easy time dealing with ice-covered marshes, swamps, ponds, and lakes. Great Blue Herons are an exception, as many of them have found they can get plenty of fish to eat along rivers and Long Island Sound. They can often be found downstream from hydroelectric dams like Shepaug and Stevenson because the water usually remains open all winter. Their closer proximity to Litchfield and Morris throughout the winter means that Great Blue Herons are the first wetland birds to arrive back here in the spring. In most years their arrival starts around the first of March, but this year we didn't see the first ones until March 15. That had to be due to ice conditions and the awful weather of the previous 4 months. With winter loosening its grip and ice finally melting over the course of the rest of the month more Great Blues appeared. Most of the sightings were initially around Bantam Lake, but they soon expanded to include the Bantam River. The first Great Blues appeared at Little Pond on 3/31 of this year. They are now being seen almost daily at Bantam Lake or somewhere on White Memorial property. A few of the birds at the North Shore Marsh are exhibiting territorial behavior, so they might nest there again this year, as they have for the past 2 years. Unlike many of their kind which choose nesting sites high in dead trees in marshes, our Great Blues seem to prefer to nest low in clumps of live Red Maple trees. That makes them really hard to see, despite their large size. Even harder to see are American Bitterns, Virginia Rails, and Soras; all of which have arrived back at White Memorial this month. Our first (and only so far this year) American Bittern was seen in the N. Shore Marsh adjacent to the Litchfield Town Beach on the 7th. Our first Virginia Rail of 2011 appeared at Little Pond on April 8th. In some past years we have seen our first one as early as March 18th. In the past few days as many as 5 Virginia Rails have been seen or heard there, despite flooded conditions. I had 5 (probably different ones) at Hamill Marsh this past Saturday, 4/23, along with our first Sora of the year. This is the earliest date of spring arrival at White Memorial that I can ever recall. Last year, we saw our first one 4/30. The Virginia Rails will stay here to breed as long as the flooding subsides. They nest low in cattails, so they are very vulnerable to flooding. For the past several years one or two pairs of Soras have exhibited some breeding evidence at Little and/or Cemetery Ponds. About 4 years ago we saw newly fledged young at Cemetery Pond. From 5/1 through 8/31 we try to survey for wetland birds in our marshes. We focus most of our efforts on Little Pond, but we should try to get to all of our marshes over the course of the breeding season. To that end, our readership can help by reporting any wetland birds that they encounter on White Memorial property. I usually go out in the evening to survey for these birds, and I welcome help.
Double-crested Cormorants
Photo by Leo Kulinski, Jr.,
Double-crested Cormorants are fish-eating birds that have undergone a phenomenal population increase throughout North America over the past 25 years. Prior to that, they were relatively uncommon due to a combination of persecution by humans and environmental contamination by pesticides. With full protection under federal and state laws, coupled with laws forbidding the use of DDT and other pesticides, the populations of D.c. Cormorants, Bald Eagles, Ospreys, and many other birds have rebounded, and then some. The D.c. Cormorants have become so numerous in some places that they have become a problem for some other species. They are colonial nesters, so they like company, not only of other cormorants, but also of herons and egrets. Unfortunately, they have ruined some of these mixed rookeries for other species by their defecating habitats. Their poop is so foul and acidic that it kills the vegetation it coats. Herons and egrets need this foliage to protect their eggs and young from predators and too much sun. Cormorants seem to do okay under the hot sun. They do however suffer losses to predation by Bald Eagles. This has been increasing in Maine for a few years as the eagle population continues to increase and more and more of them find that young cormorants are easy prey. Eagles are also known to eat young herons and egrets and will occasionally take adults, too. Predation is less of a problem when the nests are under a sufficient amount of vegetative cover. Cormorants also annoy fishermen by eating lots of fish. In an effort to address the increasing number of complaints about cormorant behavior and their huge population increase, the U.S. Fish and Wildlife Service has granted special permits to state wildlife agencies to abort eggs either by addling (shaking) or by coating them with natural vegetable or mineral oils. This is a humane way of trying to bring their population under control. This species isn't trying to nest yet at Bantam Lake, but it could. They are common as nesters on Lake Champlain, in some of New York's Finger Lakes, and all around Long Island Sound. They seem to do equally well in freshwater as in saltwater. We have seen a steady increase in the numbers of D.c. Cormorants passing overhead and stopping at Bantam Lake and Little Pond during the spring and fall migrations for the past several years. The total of 33 that we counted in North Bay this past Friday 4/15 might be a record high for Bantam Lake. Every year more and more non-breeding individuals of this species stay throughout the summer at the Lake. It will be interesting to see what happens if they start breeding here. If you see these birds carrying sticks or sitting on definite stick nests on rocks or on the ground or in trees or shrubs (they will nest in all of these situations) please notify me via e-mail, which is dave@whitememorialcc.org.
Wildlife Management and Inventorying Activities, 4/14/11
The Migrants Continue to Pour in to Litchfield
A Flood of New Migrant Birds in Litchfield
Ospreys have returned to Bantam Lake
Living Fossil Discovered at White Memorial!
Chewed stumps from North American Beaver (Castor canandensis), left, while the tall stump to the right is evidence from Giant North American Beaver (Castoroides ohioensis). |
Camera caught image of Giant North American Beaver on White Memorial Property. |
April Fools! The tall stump is the remains of a tree gnawed by a North American Beaver (Castor canadensis) while standing on two feet of snow this past winter on the property.
http://en.wikipedia.org/wiki/Castoroides_ohioensis