The Chesapeake Bay and its great tidal rivers
join to form the largest and most productive estuarine

complex in North America. They supply

vast amount of nutrients into coastal waters and

provide a huge spawning and nursery area for

many species of fish.

The warm waters of the Gulf Stream flow north

along the East Coast until they collide with the

cool, plankton-rich waters of the Labrador

Current flowing south. The intermixing of these

currents occurs near Cape Hatteras, North

Carolina, and in adjacent waters. This puts the

southern coast of Virginia in the dynamic area

where the Mid-Atlantic Bight and South Atlantic

Bight are joined, and brings a huge mix of finfish

species into local waters. In fact, Virginia is the

southernmost range of real abundance for many

temperate species of fish and the northern range

of abundance for many subtropical species.

The large peninsula which forms the Eastern

Shore of Virginia is flanked by a chain of uninhabited

and unspoiled barrier islands.

These islands protect a rich complex of

marshes, bays and sounds which provide a

haven for a variety of marine life.

The main portion of the Chesapeake Bay follows

the ancient bed of the Susquehanna River.

Dramatic forces during the Ice Age, which helped

shape the Susquehanna Valley, and the rising

ocean waters caused by the melting ice cap as the

Ice Age ended, transformed the southern portion

of this river valley into the vast estuarine complex

that today is the Chesapeake Bay.

The Chesapeake Bay continues as the place

where several of the great rivers in the eastern

United States meet the ocean. The Susquehanna

River has the greatest impact on the Bay contributing,

on average, almost 50% of the freshwater

flowing into the Bay. The Potomac and the James

Rivers provide more than 15% each, leaving under

20% for the combined inflows from more than a

dozen other rivers including the Rappahannock,

York, Chester, Choptank and Nanticoke.

Water also flows into the Chesapeake Bay from

the ocean. A relatively constant inward flow of

ocean water occurs along the bottom at the

mouth of the Chesapeake Bay. These ocean

waters, laden with salts and minerals, are heavier

and more dense than the freshwaters flowing

from the rivers into the Bay and out its mouth in

the upper portions of the water column. This pattern

of water circulation, with heavier saltwaters

flowing into the Bay along the bottom while

lighter freshwaters flow out near the surface,

was documented in a scientific study by the

Virginia Institute of Marine Science.

The mixing of ocean and rivers waters in

the Chesapeake Bay produces waters which

are variably salty and fresh, often changing

based upon short term weather phenomena,

long term weather or climatic patterns, tides,

depth and location. However, certain patterns

remain constant. Bay waters along the eastern

side of the Bay are saltier than waters along the

western shore. This is due in large measure to

the large inflows of freshwater from the western

rivers and a phenomenon called the coriolis

effect – a result of the rotation of the earth.

Tides, which are caused by the rise and fall of

ocean waters due primarily to the gravitational

forces of the moon and the sun, cause variations

in salinity. During high or rising tides salinities

increase in the Bay and move further up the Bay,

while the opposite occurs on low or falling tides.

Since tidal movement originates at the mouth of

the Bay (tides are the rise and fall of ocean

waters), the times of the peak high and low tides

vary by location. The "wave" of tidal flow starts at

the mouth of the Bay and must physically move

to its upper reaches and up its tributary rivers.

This takes time and the difference between the

time of the high tide at places near the mouth of

the Bay and others farther up the Bay or in the

tidal portion of its tributary rivers can vary by as

much as 4 – 6 hours.

Forces with seemingly little connection to the

Chesapeake Bay can have major impacts on

salinity levels. For example, heavy rains in western

Virginia, Maryland and Pennsylvania mountains

may create flash floods which can send

pulses of freshwater down major rivers. These

pulses are called "freshets" as they reach the

brackish waters of the rivers near the

Chesapeake Bay, and these sudden changes in

salinity can have pronounced impacts upon

marine life. In fact, the torrential rains in

Pennsylvania during Hurricane Agnes in 1972,

creating epic floods from the Susquehanna River,

had catastrophic effects on the Chesapeake Bay.

In fact, Agnes may have been the "trigger" mechanism

for the disappearance of vast areas of

underwater sea grasses in the Bay. Unfortunately,

the sea grasses have not been able to recover,

probably due to the combination of pollution,

excess nutrients and turbidity associated with

water quality problems.

Changing salinty levels are not the only dynamic

forces impacting the Bay environment. Water

temperatures vary dramatically on an annual

basis. The water temperatures found in the

Chesapeake Bay probably have the highest average

annual variance of any location on the East

Coast. Winter often produces skim ice and even

harder freezes on the lower Bay tributary rivers,

and several times in this century portions of the

main stem of the Chesapeake Bay have been

covered with ice. Summertime surface water

temperatures in shallow bays may approach,

or exceed, 90 degrees. Sudden changes in

temperature, which may occur during

extended cold snaps in the fall or early winter,

can cause water temperatures to drop dra-

matically resulting in severe stress to fish and

other marine life.

Even events outside of the Bay can impact its

water temperature regimen. Heavy snowfall early

in the fall in the Blue Ridge mountains can result

in a drastic lowering of the water temperatures in

the tributary rivers running to the Bay. As these

rivers feed into the Bay, the water temperature

can be lowered rapidly with often severe impacts

on marine life.

For these reasons, the marine life found in the

Chesapeake Bay is among the hardiest and most

adaptable found anywhere in the world.

While life in these dynamic surroundings is not

easy, estuarine environments are extraordinary in

their richness and diversity of life. Most of the

commercially and recreationally important finfish

species of Virgnia spend a portion of their lives in

an estuarine environment.

Estuarine communities begin with intertidal

salt marshes. These low areas, characterized by

muddy tidal flats, spartina grasses, and small

creeks, are nature's "buffer" zones. They provide

filtering areas that trap nutrients and, in recent

years, pollutants, preventing them from overburdening

the tidal rivers and bays. The tidal

marshes are teeming with life from the everpresent

snails, fiddler crabs and worms to

shrimps, "fundulus" minnows, blue crabs

and juvenile fish.

Unfortunately, intertidal salt marshes and

wetlands have been disappearing in modern

times due to the increasing pressure to

develop waterfront properties caused by the

desire of more people to live near the coast.

While this trend continues, the rate at which

marshes and wetlands have been declining is

slowing, as regulations have focused efforts on

environmentally "friendly" development which

provides protection for these critical and sensitive

areas. Increased protection of tidal marshes

and wetlands is a key component in maintaining

the water quality of the Chesapeake Bay and preserving

much of its marine life.

Sea grasses, mainly eelgrass, thrives in shallow

waters, often growing best in waters that are

somewhat protected from excessive wave and

current movements. They provide protection for

many small fish and molting blue crabs, making

this habitat attractive for numerous game fish.

In addition, sea grass beds serve a filtering

role, helping sediments to trickle to the bottom

which produces better water clarity. Sea grass

beds dissipate wave energy, which helps to

reduce shoreline erosion and improves water

clarity. Ironically, many scientists believe excessive

runoffs, a form of non-point source pollution

which causes increased water turbidity,

was responsible for killing many sea grass

beds in the Chesapeake Bay during the

1970’s, probably triggered by the torrential

rains and massive floods associated with

Hurricane Agnes in 1972. Thus, while sea

grasses are important in preserving and improving

water quality, it may have been poor water

quality which killed massive sea grass beds 30

years ago.

During the last fifteen years, however, the

Chesapeake Bay clean-up initiatives have focused

on controlling agricultural and urban runoff, and

sea grass beds are starting to make comebacks.

In many ways the health of sea grass beds may be

a good measure of the health of the Bay, since

sea grasses require good water quality, low in suspended

sedimentary runoff, nutrients, pollutants

and phytoplankton, to thrive.

Oyster rocks and bars are the major types of

natural "reef communities" in the Chesapeake

Bay. A host of small invertebrates are attracted to

the oyster rocks and contribute to the food chain.

In turn, these "live bottom" areas attract a host of

small finfish, which are sought out by even larger

game fish.

Oysters are filter feeders, straining small plankton

and nutrients from the water column, which

is an important component of maintaining the

Chesapeake Bay's water quality. At the start of the

20th century oyster rocks rising ten feet off the

bottom were not uncommon. Oysters were so

numerous they were thought to be able to filter an

amount of water equivalent in volume to the

entire Chesapeake Bay in less than a week.

Disease, pollution and overharvesting have

reduced oyster populations to a fraction of that

level, and today’s population of oysters would

take nearly a year to filter the water volume of the

Chesapeake Bay. Rebuilding the oyster population

is a major priority of fishery managers in

Virginia.

Another concern in recent years has been a

declining trend in some of the prime forage fish,

especially menhaden and bay anchovies, in the

Chesapeake Bay. Menhaden are the other major

filter feeder associated with the Bay, thus serving

a dual role as forage for many important recreation

fish and a component in the Bay water

quality equation. Observers are unsure whether

this decline is a short term phenomenon or a

longer term problem, but efforts are being mobilized

to investigate this issue.

The Chesapeake Bay offers a tremendous variety

of recreational fishing opportunities, but no fish

is more symbolic of the Bay than the striped bass.

The Chesapeake Bay is the largest spawning

and nursery area for striped bass on the East

Coast. As much as 80% of the coastwide migratory

population is thought to be native to the

Bay.

Striped bass, like shad and herring, are

anadromous; this means they spend the

majority of their lives in saltwater but return

to freshwater rivers to spawn. They can be

caught in virtually every portion of the

Chesapeake Bay and its tributary rivers. In addition,

stripers can be found at some place in the

Bay every day of the year. The resurgence of

striped bass populations in recent years from the

population collapse in the 1970’s, which nearly

culminated in their listing as a threatened

species, is one of the spectacular success stories

of modern fisheries management.

Striped bass provide just one of several opportunities

for small boat fishermen to do battle with

adversaries which may weigh 50 pounds or more.

In addition, the Bay offers seasonal runs of cobia,

red drum and black drum. Red drum and black

drum appear in Bay waters in mid-April, while

cobia usually appear on the Memorial Day weekend.

The reappearance of seagrass beds in several

locations in the Bay may be the reason speckled

trout populations have grown in recent years.

Since the late 1980’s, speckled trout populations

have been increasing, and the favorite haunts of

this popular game fish are shallow water flats with

abundant seagrass beds.

The Chesapeake Bay is a summertime home

for many species of "panfish". Summer flounder,

croaker, spot, and small gray trout are the

favorite targets for many anglers bouncing baits

along the bottom. Spanish mackerel and small

bluefish can be taken by a variety of methods

using artificial lures and bait, and in

recent years anglers have started to learn the

methods which are productive for catching the

visiting populations of spadefish and

sheepshead. The reappearance of some larger

gray trout is welcome news for recreational fishermen

approaching the new millenium and is

another example of the positive contributions of

serious fisheries management.

Tautog can be found over wrecks and obstructions

in the lower Chesapeake Bay all year but are

most active when the water is cool. They remain

active throughout the winter, as long as water

temperatures remain in the low 40’s, or higher.

Black sea bass can be found in the same areas

from late spring through the fall.

REF: Virginia Saltwater Angler’s Guide, Prepaired for the VMRC