Being Valuable before School Starts

It is Labor Day weekend. August is coming to a close.

(A Lookdown fish - a sometimes tropical visitor to local bay waters this time of year)

Look closely and you will find hints of autumn. The fist blush of some leaf color is already taking place in some upland locations from Tupelo or Blackgum trees and Poison Ivy bushes. These two plants are some of the first to provide an early blast of fall color to shore surroundings. Moreover, if you glace down along the ground, you might see a Chipmunk starting to hoard food for winter. Some people have told me they have observed a single Chipmunk stuff up to 31 large corn kernels or between 60 to 70 sunflower seeds in their tiny cheek pouches. Now that is amazing!

Down by the bay, the physical environment is just as dynamic. Look for many transient tropical fish to arrive as they follow the Gulf Stream northward and enter our neighboring bay waters that are warm; somewhere between 74 and 78 degrees. A few of the strange and colorful tropical fish to turn up around here might include Butterfly fish, Big Eyes, Lookdowns, or Angelfish.

(A secretive Green Heron scanning bay waters for a fishy meal)

In bay waters, there are also great swarms of resident small fish, such as different species of silversides or spearing, herring, and killifish. They are in great abundance now as the small fish feed in large schools either in tidal salt marshes, open bay waters, coves, or along shorelines and beaches.

Small fish, such as Rough Silversides, Blueback Herring, and Striped Killifish    are considered by many scientists to be of great value as forage or food for bigger fish. It is all part of a productive and thriving estuarine food chain, which I am sure many of you remember from primary school.

Larger fish such as stripers and blues are active in and off-shore waters and rely on a variety of small fish to feed on for their survival. It is the start of migration time for many species of large fish. As these dominant aquatic predators begin to move out of the bay and swim southward to warmer waters, they require large amounts of food to fatten up.

(A Great Blue Heron foraging bay waters for small fish to eat)

Indeed, a fleeting look at bay waters may provide a stunning "Bluefish blitze" encounter. Bluefish feeding binges can happen anytime. Look for tiny fish to all of sudden jump or "fly" high out of the water to escape being eaten. Know as "blitzes," these surf spectaculars are feeding frenzies that Bluefish use to fuel energy needs for their annual lengthy migration southward to between Cape Hatteras to Florida.

Estuarine birds too get in on the action feeding on tiny fish and crabs. Many birds seen in the bay are dominant predators that are high up on a food chain. Small shorebirds including Common Terns, Least Terns, Black Skimmers; and large wading birds such as Snowy Egrets, Green Herons, Black-crowned Night Herons, and Glossy Ibises all depend on large schools of Silverside fish and KIllies or on an abundance of different species of crabs, such as Blue Crabs and Fiddler Crabs, to fuel their energy needs this time of year. The birds must feed and fatten as they begin their winged migration southward before the winter. 

(This time of year local bay waters are full of baby crabs, such as this juvenile European Green Crab)

Out for an early morning kayak outing the other day, I was greeted by many Great Blue Herons, Great Egrets, and even several secretive Green Herons. They didn't seem to care too much about me being around. The birds were hard at it catching killifish along the edge of a marsh.

I also saw quite a few ospreys circling and feeding just off the lower portion of the Navesink River. Early fall is when Ospreys seem to be around this area in great numbers. Most of this activity is due to fall migration, birds that have nested from Canada and northern New England, from Lake Ontario to Lake Champlain, are heading south now. Ospreys or Fish Hawks stopover in New Jersey to rest and feed at the same time as big Bluefish push large schools of tiny fish closer to the surface to feed on, and huge aggregations of small fish, such as menhaden are just the right size to be plucked from the bay.  In fact, one adult Osprey flew by me overhead with about a 6-inch silvery herring snack in its talons.

What provides the fuel for all this activity to take place in the bay? Believe it or not, in one simple word the answer is - plankton. Yes, those tiny little unseen critters that you often hear, but never see. Tiny microscope plants and animals really help to create a productive bay.

(A tiny first-of-the-year Striped Killifish recently caught in a net out of the Navesink River)

It begins with organic matter entering the bay over the summer from many different sources, including salt marshes, mud flats, sandy beaches, forested wetlands, and upland forests. As wind, rain, and tides mix these surface nutrients with deep water nutrients from the bay and ocean, the motion creates a "fall bloom" of plankton activity. This bloom is just in time for autumn migration that requires many species of birds and fish to feed and get fat on small fish, which in many cases solely survive on plankton. It is amazing how Mother Nature has timed this productivity to occur in the bay so well.

Thousands upon thousands of fish and birds will migrate through the Raritan Bay and Sandy Hook Bay watershed region. A person may not see all the fish and birds this season, but many will pause here to relax and feed on their way south for the winter.

So, as many folks start to enjoy the sights and sounds of birds and fish migrating along the Jersey Shore, let's not forget that the journey is complex, tiring, tough, and often easier said than done. In the end, though, it is the great amount of energy to be transferred from vast swarms of plankton that will, in part, help to feed and support huge populations of migrating animals and create a productive, dynamic, and exciting bay this fall. Gee, have you hugged a drifting plankton critter today?