What's Happening on the Hudson River in August
We think of August as a fairly uniform time of languid days, warm sun, gentle breezes, and singing cicadas and katydids. However, compared year-to-year, August is a month of contrasts. In 1999, August baked the Hudson Valley in the worst drought in 105 years. Drought caused fires and reduced freshwater tributaries so much that saltwater pushed its way up to Hyde Park, 82 river miles north of the Manhattan Battery. The next August, cool, damp weather had the river 4-6 degree Fahrenheit cooler than the previous year. Salt was barely detectable north of the Hudson Highlands.
Summertime water temperatures and precipitation are both key factors in the growth and distribution of Hudson River fauna. Warm, brackish water increases the rate at which young fish and blue crabs grow; cool water temperatures slow that growth. Crabbing season in upriver freshwater areas lags about two months behind downriver brackish waters primarily due to the age of the crabs: the lower Hudson is dominated by older, larger crabs, upriver is the primary domain of one-year-olds. They require extra time to achieve "keeper size," at least five inches across their carapace. However, time is a great equalizer. By October the blue crabs, shad, herring, and bass all reach their usual autumn proportions.
Similarly, the ranges of river fish fluctuate as August conditions vary from year to year, and week to week, as the freshwater and saltwater species shift up or downriver in accordance with changing salt levels. Increased saltiness should bring coastal species such as summer flounder, bluefish, and weakfish up into the river, as far as Dutchess and Orange counties. At the mouth of the estuary, the reservoir of salty sea water in the New York Bight between Long Island and New Jersey moderates the fluctuations caused by freshets from the uplands.
However, in August we begin to see the effects of another "river" - the Gulf Stream - on the Bight and the estuary. This wide band of warm water flows northward from the tropics. Each summer, tongues of this current spin off toward shore, depositing eggs, larvae, and juveniles of many marine species on our doorstep. Many of these are usually associated with warmer temperate or even tropical waters. Past finds include young bonefish and permit, both prized gamefish in the Florida Keys, and colorful reef fish such as spotfin butterflyfish and spotted trunkfish. Add to these exotics the many jacks, inshore lizardfish, pigfish, pinfish, and occasional sea turtle or small barracuda, and you begin to wonder why there are no coconut palms growing along the lower river in August.
Throughout the region, many young birds start making their own way in the world. Backyard bird feeders are frequented by wobbly fliers and rough landings. For predators, this is a season of plenty, but most fledglings will survive these early trials. In the Adirondacks, one of the most interesting sights of August is watching young ravens being schooled by their parents in raven etiquette. This includes where to perch to get the best view, when to call and when to be silent, and how to rob unwary campers. As the month goes by, the numbers of songbirds and warblers, will dwindle as some get an early start on their trips south. Many of these birds migrate at night, and their chirps will drift down from starry skies.
The summer sun is ripening fruit and berries across the Hudson Valley, which will be ready for harvest in August and September. Berry patches bring to mind black bears. Hikers in the Hudson Highlands, Catskills, and Adirondacks may see a few this summer. Look quickly, because often the second they sense your presence they become a black blur tearing through the brush out of sight. Black bears are not pets. Do not attempt to feed them or get close to them. They are wild animals native to this region; they were roaming these hills long before we got here. Eating is serious business for these bears, and learning to raid campsites, or trash cans, can turn dangerous. If they are cornered, threatened, or disappointed when that bag of marshmallows runs out, they will have no compunction in chasing you up a tree, or worse. Appreciate the fact that they have been able to coexist with us in the Hudson Valley without being extirpated, but respect their wild nature and leave them alone. When bears get used to people, it can only turn out badly for both parties.
Speaking of people, the trails in the High Peaks of the Adirondacks are most crowded in August, but early day hikes to Marcy, Algonquin, Iroquois, and others summits have their payoffs. The days can be scorching - wear a high SPF sun screen and sunglasses; at 5,000+ feet, the sun's effects are not to be taken lightly. Evenings will be cooler, and some of the very best nighttime skies will lull campers to sleep.
August is a prime vacation month, and many folks travel widely during those precious weeks off. But don't forego the pleasures of the eighth month near home in the Hudson Valley. The sounds of summer are never more evident, the chills of winter never seem farther away, and it showcases, year after year, the diversity of the Hudson Valley's natural history and climate.