Hudson River Almanac August 24 - August 31, 2011
While Hurricane Irene dominated the week, there were events and observations before, during, and after the storm that were not included in our recent Irene "special edition."
HIGHLIGHT OF THE WEEK
8/25 - Fishkill, HRM 61: I noticed some movement among the leaves and branches in the lilac shrub just outside the window. Out flew a cardinal headed toward our feeders. But there was still some commotion in the lilac. It was then that I noticed a male golden-winged warbler gleaning insects from the leaves. The view was ever so brief before he flew away, but it was a first for me.
- Ed Spaeth
NATURAL HISTORY NOTES
8/24 - Green Island, HRM 153: Purple loosestrife bloomed in rows along the shore in stout stands growing right at the high tide mark, giving a glow to river. An angler named Alex was fussing with his line and echoing a sentiment that we all share about the many "hang-downs" that claim our lures. Alex's lure was lost out beyond the tide line, hung down on an old bedspring. He told me of his recent catch, a 43-inch-long "northern pike." Even allowing for exaggeration, that was a whopper - a record fish. I offered that it may have been a tiger muskellunge. No, it was a pike! With no photo, the catch becomes an enigma. The river was 75 degrees Fahrenheit.
- Tom Lake
[Purple loosestrife has negative effects on some species and positive effects on others. Large areas of dense loosestrife are not good for many of the marsh birds and for many other plants (although some plants do well beneath and between the loosestrife where they are hard to see). Loosestrife, on the other hand, supports a lot of flower-visiting insects (honeybees, native bees, butterflies, moths, etc.) with a rich supply of nectar and pollen. Loosestrife nectar may be especially important during dry periods when many other flowers are not doing well. Loosestrife also supports many leaf-feeding insects (these tend to be species that are generalists feeding on multiple kinds of plants). Two such generalist leaf feeders are the Cecropia and Polyphemus moths, two of our largest North American moths; loosestrife seems to be beneficial for them. Robust clumps of loosestrife support mosses and liverworts, as well as the nests of several songbird species and both common and rare species of parasitic dodder vines. The golden loosestrife beetle is not the only factor in the reduction of loosestrife biomass. A native beetle, the water-lily leaf beetle, and white-tailed deer are also contributing to loosestrife inhibition in some areas, as are increased water levels and livestock grazing. Erik Kiviat.]
8/24 - Hyde Park, HRM 82: A dawn check on the gray seal produced no results. He was likely out foraging. The river temperature (76 degrees F) was beginning to drop, down six degrees from its mid-summer high. As the seal lingers, we begin to speculate on what factors might inspire him to head downriver to the sea.
- Tom Lake
8/24 - Town of Poughkeepsie, HRM 73: I went for a walk along trails on the Locust Grove grounds to a place where you can view the Hudson. A large bird circled above the opposite bank of the river; taking a closer look through my camera I saw that it was a bald eagle. It circled across and down my side of the river, no more than 200 yards from where I stood. It seemed to dangle in midair before landing on the river to grab a fish. It was wonderful to watch and it was the first time I had ever had the pleasure of observing a bald eagle hunting. Ten minutes later an osprey flew past, also doing a bit of fishing. That was another first for me, having never even seen an osprey before.
- Jamie Collins
8/24 - Wappinger Creek, HRM 67.5: For all their ecological drawbacks, the large and heavy mats of water chestnut provide a hunting and feeding perch for wading birds. I watched a snowy egret meticulously pick and choose its openings in the vegetation while snatching small fish from the shallows beneath. The bird's yellow feet - "golden slippers" to birders - were striking.
- Tom Lake
8/25 - Kowawese, HRM 59: The wind was strong out of the southeast, portending much rain. Black clouds settled over Storm King, again reminding us of the appropriateness of its name. The late summer season as well as the wind and tide had already marked the successive high tides on the high beach with rows of uprooted wild celery.
- Tom Lake, TR Jackson
8/26 - Town of Poughkeepsie, HRM 75: As I walked in shadows along the Fall Kill, I thought I saw a hummingbird heading my way. It was a giant swallowtail butterfly. On average, they are slightly larger than the more common tiger swallowtail. While generally uncommon in the Mid-Hudson Valley, this was at least the fourth sighting this summer.
- Tom Lake
8/26 - Croton-on-Hudson, HRM 35: La Reina de la Noche, also called night-blooming cereus, performed last night. The bowls of her glorious white blossoms measured 8-9" across. Adding the pink finger petals which fringe the bowl, the full blossom's measurement was close to 13". There were seven wide-open blossoms scenting the air so that even on the other side of the house I was carried to sleep by their perfume. I gave up adoring La Reina at about 9:30 PM as it was muggy, buggy, and oppressively dark outside. This morning the world was ominously still. La Reina was finished for the season, her spent blossoms drooping from her strap-like leaves
- Robin Fox
8/26 - Piermont Pier, HRM 25: We walked the pier just before low tide this afternoon to look for the Hudsonian godwit that had been reported the day before. The godwit was absent, but we spotted semipalmated plovers and least sandpipers and watched a juvenile black-crowned night heron follow an adult across the mud to a tide pool. Other than its orange legs, the juvenile was superbly camouflaged against the background of breakwater rocks. At one point the adult halfway submerged itself in the tide pool so just its back, neck and head were visible. Was it trying to cool down? It emerged some minutes later and shook itself off.
- Linda Pistolesi, Margie Turin
8/28 - 8/31, Hudson River Estuary: While human observers recorded the unusual sightings highlighted in last week's Hurricane Irene special issue, Hudson River Environmental Conditions Observing System [HRECOS] and U.S. Geological Survey [USGS] sensors were accumulating data showing the storm's broad physical impacts on the estuary. In some cases, we can predict how these will affect river life. Mortality among oysters in the river off Westchester will likely be high, for example. But as often as not, we are left with questions. How will submerged plant beds react as life-giving sunlight is blocked by muddy water; will they be affected not only this fall but next year? And what about our celebrity visitor - the gray seal in Hyde Park? Will it be able to find food in the turbid, nearly opaque waters of the Hudson following the storm? Below are a few stories from HRECOS and USGS data; to view graphs of these and other storm-related phenomena, visit www.hrecos.org and http://ny.water.usgs.gov/projects/dialer_plots/saltfront.html.
- Steve Stanne
Storm surge: Irene's passage coincided with a high tide predicted to occur at the Battery [HRM 0] shortly after 8 AM on Sunday, 8/26, and to roll up the river, reaching Poughkeepsie [HRM 75] at about 12:45 PM, and Albany at roughly 5:15 PM. Storm surge, enhanced by the low barometric pressure associated with Irene, added nearly four feet to the average high tide height at the Battery. At Poughkeepsie, the river level was three feet above flood stage and rising at midday when the USGS gage suddenly stopped recording; by that point, the playground at Waryas Park had become a water park. At Albany the high tide peaked just over flood stage at 11 feet above sea level in late afternoon. As the tide started down, river level fell only to about 10.5 feet before runoff took over and sent it up again, cresting at 15.4 feet on Monday evening, 8/29.
Flooding due to runoff: Catastrophic flooding caused by Irene along the Hudson's tributaries has been well-described in the media. However, the mainstem is usually at sea level virtually all the way to Troy [HRM 153]; flood water runoff volumes are rarely sufficient to raise the water's surface above sea level further south than Catskill [HRM 112]. Irene's deluge provided an exception to this rule. River level was well above average until Wednesday, 8/31, at West Point [HRM 52], for example.
Turbidity: The rush of sediment-laden runoff into the estuary was visible in photographs from satellites. In the early morning hours Sunday, 8/28, turbidity readings at the HRECOS gage in Albany were about 3 NTU [nephalometric turbidity units - a measure of the degree to which light is scattered by particles suspended in water]. By midnight, turbidity had increased to nearly 140 NTU. On Monday afternoon, it maxxed out the sensing device at 1,000+ NTU; readings stayed at the sensor's ceiling until early Tuesday morning. At day's end Wednesday, 8/31, readings were approximately 235 NTU.
The salt front: As would be expected, the salt front retreated before the onslaught of freshwater runoff from the watershed, though it took a few days. At Piermont [HRM 25] and the George Washington Bridge [HRM 10], the salty influence of sea water was swept away by the end of Tuesday, 8/30, while at Castle Point, Hoboken [HRM 4], there was a just a whisper of saltiness near the end of each incoming (flood) current in the tidal cycle that day.
8/31 - Fishkill, HRM 61: While we were talking in our yard, a bright orange and brown butterfly fluttered about our heads. It landed on our stone wall where it sat momentarily opening and closing its angled wings. As it did so we noted that it was a question mark butterfly.
- Ed Spaeth, Merrill Spaeth, John Pereira
8/31 - Piermont, HRM 25: The high tide water level at Piermont crested at noon. The pier road was flooded and water was still rushing in. A dozen cormorants were perched on one of two visible rock clusters on the north side of the pier; the second, a small point, had two cormorants challenging each other for the spot to dry out. Several ospreys were circling and swooping. One dove down and we saw a flash of silver as it caught its prey and then began a slow ascent to regain elevation and head to a feeding perch. I was surprised at how slowly it regained height but my daughter reminded me that they weigh less than their size would appear and, although it was a short flight, the added weight caused an increased energy output.
- Margie Turin, Linda Pistolesi