Friday, August 31, 2012

Shorebirds and Raptors at Delta Lake

A flock of mostly Least Sandpipers feed in the shallow water at Delta Lake
 We have few local places where migrant shorebirds can gather, which is understandable since we're located so far inland. Our closest thing to a shorebird “hotspot” is Delta Lake. In years when they draw down this reservoir’s water level, mud flats are exposed and shorebird habitat is created. Of course, just because you have the habitat doesn't mean the birds will come.

Shorebirds come in a variety of sizes, which enables the different species to forage for food in various depths
In recent years, shorebirds have not been flocking to Delta in droves. Low numbers probably reflect smaller overall populations of these species. Factors that affect their numbers include degradation of habitat on their breeding grounds, wintering grounds and at their migratory stopovers. Of course, the vast majority of shorebirds migrate along the coast, so in a way, we are lucky to see any at all in our area.
The Semipalmated Sandpiper is often quite common in mixed shorebird flocks
Though Delta has been known to bring in a few regional rarities over the years --birds like the Marbled Godwit and the Buff breasted Sandpiper, in recent times we consider ourselves fortunate just to locate the more common species like the Lesser Yellowlegs and the Least Sandpiper.
A Merlin perches over the mudflats and waits for a good target bird to come into view
Where shorebirds congregate you also tend to find their predators. Falcons like the Peregrine, Merlin and America Kestrel try their luck chasing down and nabbing unfortunate shorebirds. Sometimes you might infer the presence of a falcon, just by observing the erratic and restless behavior of a shorebird flock. A harassed flock might put down on a given piece of shore only briefly before taking flight again.  While retaining a tight formation, the shorebirds execute rapid changes in direction. These evasive maneuvers are similar to those employed by schools of fish.

Another Merlin watching the flats
My last visit to Delta was rather raptor heavy; I saw a pair of immature Peregrine Falcons zooming over the flats, stirring up the waterfowl and shorebirds. A one point the pair sparred with each other, but in a friendly manner –perhaps they were siblings.
One of 4 Juvenile Bald Eagles that have been seen lately at Delta
About half the size of the Peregrines, a pair of Merlin's were also present that day. Despite their small size, Merlins are fully capable of whipping shorebirds into a frenzy. They also chased after each other in a much less friendly manner than the Peregrines.
A Great Egret hunts for fish that have been stranded in the shallows
As the water gets increasingly shallow, fish often get stranded in isolated pools and this creates a draw for a diverse group of avian predators. Bald Eagles, up to 5 of them were hunting for fish –either to catch for themselves or to take from other fisher birds, like the Osprey.
Double-crested Cormorants show up to fish the Lake
Wading birds also gather in number to take advantage of the easy fishing. Great Blue Herons are the most prevalent, but Great Egrets are also fairly common. Lately, up to 6 egrets have been seen around the lake.

Lesser Yellowlegs
Waterfowl numbers continue to increase as the migration season gets underway. Many Wood Ducks and flocks of teal are already there. Black Duck and Hooded Mergansers can also be picked out among the many Mallards and the throngs of gulls.

Friday, August 24, 2012

The Remarkable Monarch Migration Begins, Also Painted Lady Butterflies Become Common at the Preserve

A Monarch nectars on blooms of the Rattlesnake Master  plant
Monarch Butterflies are pretty common this summer and currently they can be found in all different phases of their life cycle --from egg to larva, and from to pupa to adult. All around the nature preserve and throughout the region they are being seen nectaring, mating and laying eggs.
A very small Monarch egg on the underside of a Milkweed Leaf
There are also a fair number of migrant Monarchs passing through on the first leg of their incredible 2,000 mile journey to one small group of forested mountains in Mexico. It’s the season’s last generation of Monarchs that undertake this migration, and for that purpose they will live much longer than the season’s previous generations. Instead of surviving for only 1 or 2 months, these new Monarchs will live for up to 9 months, which is long enough to complete their migration and survive through the winter.

The Monarch Chrysalis 
 While traveling, the Monarchs need to make frequent stops for nectar and for water, and this is when we are lucky enough to see them. Usually, they are observed flying low over meadows and other habitats, but they are also capable of flying quite high. I’ve seen Monarchs flying where few other butterflies do –actually hundreds of feet up in the sky. They do this by taking advantage of rising columns of air, and then just like raptors, they are able to soar toward their destination without expending so much energy flapping their wings. By this method they are able to fly over 50 miles per day.

The Monarch caterpillar feeding on a Common Milkweed Leaf
This season, more Painted Lady Butterflies have been seen at the nature preserve than ever before. Their numbers don't compare with what we experienced earlier in the year with the Red Admirals, but nevertheless, it has been quite interesting.
The Painted Lady Butterfly on a Spotted Knapweed flower
The Painted Lady strongly resembles our more frequently encountered American Lady Butterfly. One easy way to tell the 2 species apart is to count the number of eye-spots present on the insects' underwing. The American Lady has 2 large eyespots, while the Painted Lady has 4 small eye-spots.
Note the 4 small eye-spots on the underwing of the Painted Lady
The Painted Lady is at home in nearly every continent in the world. They are also famous for their own large scale migrations. Every year, swarms of Painted Ladies come out of Mexico and spread north throughout the rest of North America.
Note 4 black spots on the top of  each hindwing on the Painted Lady

The main foodplants for the American Lady are Pussytoes and Pearly Everlasting --2 plants that grow in our meadows. The latter plant is especially common. The Painted Lady is much more of a generalist when it comes to its main foodplants --and their caterpillars are able to feed on the leaves of a variety of plants including many common thistles. Just this past June, I watched one of these butterflies laying her eggs on a Canada Thistle plant. Certainly if they can get nourishment from this abundant plant they will never go hungry.
The American Lady (even this damaged one), on its hindwing shows "blurred" black spots with bluish centers
 This Painted Lady Butterfly is raised commercially and often sold to people that wish to release butterflies at weddings and other functions. So whenever I see one, I wonder if it’s a refugee of one of these events. However, I think it’s safe to conclude that the generation that I’m currently seeing were born and bred locally and in the wild. 
A Gray Comma licks a stream-side stone for minerals
The underwing of a tiny Eastern-tailed Blue Butterfly

Wednesday, August 22, 2012

Early Fall Migrant Songbirds

An Ovenbird prepares to leave its breeding grounds at the nature preserve
It may be hard to believe, but at this point in August some birds already have their bags packed are close to bidding farewell to the Northeastern US.
An Immature Baltimore Oriole is ready to make its first journey south
The Baltimore Oriole is one species that always seems anxious to leave and to get to their tropical retreat. The fact is that I rarely encounter orioles after the first few days of September. This means that their entire stay with us in the North is barely 4 months long.
Blue-winged Warbler --rarely in the Northeast seen after the first week of September
Blue-winged Warblers also don’t dally long, and most of them will be on their way south before the first week of September is done. But other species of warblers continue to pass through the area -most coming from their breeding grounds in the Adirondacks and Canada. Even many of the latest migrant warblers will be gone by the 3rd week of October. After that, we won't see them again until next Spring.
A migrant Magnolia Warbler -- this individual is lacking the typical black marks on the sides of the chest
Yesterday at the nature preserve, I saw the first migrant Tennessee Warbler. This small and fairly innocuous species breeds in the forests of eastern Canada and like so many others, they only pass through Central New York during spring and fall migration.

A Tennessee Warbler as they appear during fall migration

Some people might not recognize the fall Tennessee Warbler as being of the same species as the Spring Tennessee -they look that different. In spring they have a whitish chest, dark eyeline, bluish gray cap and greenish back with no wingbars. In fall, an adult is usually quite yellow on the underside, and even has yellow on the top of its head and on its wings and back. Though some individuals may retain a muted version of their spring colors.

The Philadelphia Vireo's plumage resembles that of the fall Tennessee Warbler
The Philadelphia Vireo bares somewhat of a resemblance to the fall Tennessee Warbler, and both species may occur together in a mixed flock of foraging songbirds. The vireo's noticeably heavier bill is a good distinguishing trait to look for in the field, since the Tennessee Warbler's bill is narrow even for a warbler.
The male Northern Parula looks a little duller in its fall plumage, but is still quite a colorful bird
The Least Flycatcher has begun showing up in mixed foraging flocks. This small, relatively non-descript member of the flycatcher clan is closely related, and strongly resembles 2 of our summer resident flycatchers –the Alder Flycatcher and the Willow Flycatcher. However, the Least, as its name implies, is noticeably smaller and it tends to linger longer into September than do the other 2 species. Some Least Flycatchers breed in the area, but not at our nature preserve.
A migrant Least Flycatcher tries its luck catching bugs along the trail-side

The Olive-sided Flycatcher is another early season migrant. However, we often go several years without seeing one of them during their migration period. This is due to their species population being relatively small -at least when compared to some of the migrants already discussed. The Olive-sided Flycatcher breeds in the Adirondacks and places north –usually in close proximity to bogs and wooded swamps.
The Olive-sided Flycatcher perched over one of the beaver ponds

Sunday, August 19, 2012

American Chestnut and 2 kinds of Skullcap –Mad Dog and Downy

An American Chestnut Trees grows in  one of our preserve's reforestation fields
Over the last 13 years, over 10 thousand trees have been planted at Spring Farm CARES' nature preserve. Most of these native trees are intended to provide food and shelter for our resident wildlife; a few of them are relatively uncommon in our region. Probably the most uncommon of all of these is the American Chestnut.
The unusual flower spikes on the Chestnut branches
Once a major constituent of eastern forests, the American Chestnuts were killed off by an introduced blight that spread rapidly through the country over century ago. The loss to the Eastern forest was incalculable, as so many species of wildlife depended on the trees for habitat and for their reliable annual production of nuts. Unlike the introduced Asian chestnut trees, the American Chestnut was an exceptionally tall tree and its branches were able to take their place in the highest forest canopies in the eastern US.
The green, prickly seed pods of the American Chestnut

A decade ago, I planted about 20 Chestnuts into our reforestation fields. For the last 3 years, a few of them began producing flowers; and this year, for the first time, one of them is producing nuts --not many, but it's a start. The nuts are encased in green, heavily spiked pods. Currently, the spikes are soft, but as the nuts within them mature, they turn brown and stiffen. At that point they are something that you might want to handle with some care.

Though as far as I could determine, the American Chestnut was not a species that was ever common in the Mohawk Valley, though historically, it did occur in the regions all around us (except in areas to the north). I thought that the addition of this species to our forest could possibly help to make up for the anticipated loss (from another exotic blight) of our American Beech Trees.

A Hazelnut, encased in its leafy husk
Generally, this has not been a good year for most of the nut producing trees at our nature preserve, and I suspect, throughout the greater region. Few if any of our young oak trees appear to have acorns this season. Beech Trees, which produced a reasonably good crop last year, also appear to be quite barren this year. On the other hand, the Hickory Trees have produced nuts, though our common species, the Bitternut Hickory, produces bitter nuts that are not typically favored by wildlife.
A Black Cherry Tree - covered with blossoms
This past spring I planted a grove of Hazelnut Trees near our wildflower meadow. The Hazelnuts grow into small brushy trees and can produce a decent crop of nuts. Our biggest Hazelnut tree on the property only just started producing nuts last year.
Black Cherry blossoms
Fruit producing trees, for the most part, definitely didn’t experience a banner year. One notable exception would be the Black Cherries. In our reforestation fields, the branches of these young trees are actually weighed down by their bountiful production. Believe me, the birds didn’t fail to notice this.
Black Cherries, starting to turn ripe

Downy Skullcap grows on a trail side
Some interesting wildflowers are blooming now at the nature preserve. Many are native species that we introduced into different habitat niches around the property. Downy Skullcap is a member of the mint family. At the preserve, it grows on one dry, south-facing hillside where it is surrounded by Purple Coneflower and goldenrod.
Mad Dog Skullcap, growing alongside a stream
Living in nearly opposite habitat conditions is Mad Dog Skullcap, which grows in drenched soil, like that found at our beaver wetlands. Alongside the Mad Dog Skullcap plants are Turtlehead, Square-stemmed Monkey Flower and Smartweed.

Tuesday, August 14, 2012

What's New With the Beavers and Their Habitat & The Release of a Rehabilitated American Bittern

Anxious beaver kits come up onto shore
All seems to be well with our beaver colony --at least with the 7 family members that remained with us following the dam collapse at their former main pond. The 4 new kits are getting noticeably bigger, though they are still easily dwarfed by their mother and 2 older siblings.

2 beaver kits engage in a playful shoving match
The 2-year old beaver named Blueberry, has become quite proficient at obtaining food, and I, as an honorary beaver, do my part to drag a few branches down to their pond whenever I pay a visit. I think that it's the least I can do to help make restitution to this species that experienced almost unparalleled exploitation at the hands of people. In fact, by the first part of the 1800s, they were trapped to the point of extinction in New York State.

Beaver kits eating willow and poplar leaves at Secret Pond
I occasionally will give the young kits some pieces of carrot. 3 of them go absolutely bonkers for the “exotic” orange roots. They can't quite wait for me to put them in the water and so they waddle up on shore and park themselves in front of my chair and patiently wait for me to get them out of my bag.
One of the new kits grooms its sides while awaiting a treat
For many years now, I’ve tried to dispel the common misconception that beavers live inside of their dams, only now to be sort-of proven wrong by our own colony. The beavers appear to have made a lodge out of a portion of the 3rd Pond’s wrecked dam. That part of the dam had been mostly detached from the original structure by the big flood, and though the 3rd Pond’s dam was recently repaired, this old section was left hanging on it like a flange –protruding into the newly enlarged, Secret Pond.
A particularly crabby Great Blue Heron waits for me to leave Secret Pond
It's hard to say if the beavers are serious about turning it into a full-fledged lodge. So far nothing has been done to improve the outside of the structure. The beavers also already have at their disposal a large semi-dilapidated (but repairable) lodge at 3rd Pond and a new bank lodge at Secret Pond. Having a lodge that's attached to a dam is problematic. If there is ever another major dam collapse at Pond 3, the lodge could be washed away along with the dam. Hopefully, the beavers will come to this realization before they install their appliances in that place.
A sea of green plants now completely surround the old beaver lodge at Sarah's Pond
Meanwhile, the meadow that once was the beavers' largest pond, continues to evolve and as it does, new plants and animals are getting a foothold there. Woodchucks and Eastern Cottontail Rabbits are the latest immigrants to the habitat. Both enjoy the lush grasses and the tender new leaves of a variety of perennial flowers.

A new inhabitant of the beavers' former domain is the Woodchuck
The sandpipers have moved on since the mud flats disappeared, but Robins still remain to feed on the worms that are easy to pull out of the moist silty soil.

American Robins finding food on the beaver-meadow

Blue Vervain is growing all over the new beaver-meadow
At the release site the bittern slowly sticks its head out of the carrier
On Sunday, I released a rehabilitated American Bittern at the first beaver pond. The bittern had been in the care of Judy Cusworth at Woodhaven Wildlife Center. The orphaned bird came in to the Center earlier in the summer, and this weekend it was finally deemed ready for release back into the wild.
The American Bittern gets closer to the stream channel
American Bitterns are wading birds that primarily prey on fish and other small aquatic animals. They hunt by stealthily wading in the water and then slowly positioning their head over their (ususally swimming) prey. With a quick stab of their stiletto-like bill, they secure a meal, which they then proceed to swallow whole. 
Assuming the camouflage position. It would work better with a different background
The American Bittern is an uncommon species in our area and generally, in New York State. They are bigger than the crow sized Green Heron, but smaller than the familiar Great Blue Heron. The American Bittern is mostly brown. Its underside is light, but with brown longitudinal stripes that stretch from its head to its belly. These stripes, which actually resemble brown wetland reeds, help the bittern to blend into its surroundings. The bittern adds to the illusion by holding its beak straight up into the air --so that its beak looks like the top of a reed. Strangely enough, while holding this position, the bird is still able point its eyes directly forward to stay aware of potential dangers.