By Erik Williams
and Malia Schwartz
recreational angler in every part of the country must at one time or another
release fish. Minimum size regulations require many anglers to release
sub-legal-sized fish or "shorts." Rivers, lakes, and reservoirs
are areas where catch and release are particularly important. The increasing
popularity of recreational fishing has led to the problem of too many
people, too few fish. In some areas, only catch-and-release fishing is
allowed. The increase in recreational anglers is not just limited to inland
fisheries. Marine recreational angling is having a great impact on certain
fish stocks as well. One of the primary means of allowing all these anglers
to continue fishing and maintain healthy fish stocks is catch and release.
Catch and release, whether it is voluntary or required, must be done properly
if it is to succeed in having the fish survive. This fact sheet should
help anglers to release fish properly to increase the likelihood that
the released fish will survive.
Why Catch and Release?
With the cost of a typical
fishing trip, the uncertainties of success, and the appeal of a fish dinner,
why should anglers want to adopt the practice of catch and release? Aside
from certain regulations, such as bag limits or size limits, there are
a number of good reasons for releasing a portion of the catch alive.
First, catch and release offers
a sensible way to extend the fishing trip after a reasonable or legal
catch limit has been reached. If the trip involves a guide or charter
service, catch and release can prolong an enjoyable recreational opportunity,
giving anglers more value for their money.
Second, several recent studies
have suggested that as anglers gain expertise in a particular fishery
or fishing technique, they often develop an interest in "limiting
their kill instead of killing their limit."
Why Do Hooked Fish
Fish that are caught and released
may die for several reasons, but the two primary causes are stress and
wounding. Stress results from the fish fighting after being hooked. Internally,
the physical exertion causes an oxygen deficit in the tissues, forcing
the muscles to function anaerobically (without oxygen). This causes lactic
acid to build up in the muscle tissue, and then to diffuse into the blood.
Lactic acid acts as an acid in the blood, causing the pH of the blood
to drop. Even slight changes in pH can cause major disruptions of the
metabolic processes, ultimately killing the fish. If the fish is quickly
released, its blood pH usually returns to normal and the fish will be
unaffected. Some fish, after a long tow, may appear to live once released,
but the imbalance in the blood chemistry may kill them as late as three
days after being caught. In most cases, the means of preventing this type
of mortality is to not keep the fish in action for a long period of time,
unless the intent is to keep it.
The other primary cause of
mortality is wounding by the hook. Injuries caused by hooks can range
from very minor to lethal. The degree of injury is dependent on the location
of the hook wound. Higher mortalities will occur in fish that are hooked
in the gill or stomach areas, while lower mortalities occur in fish that
are hooked in the lip, jaw, or cheek areas. Baited hooks are more likely
to result in a gill or stomach hooking that artificial lures. Treble hooks,
for obvious reasons, will result in more puncture wounds and subsequently
higher mortalities. Barbless hooks facilitate release and decrease "out-of-water"
time, but for reasons yet unclear, may not significantly reduce mortality,
especially when used with bait.
There are other kinds of physiological
stress that can lead to higher mortalities in released fish. Fish may
not be able to adjust to changes in pressure or to higher surface water
temperatures. Also, when a fish is handled or comes in contact with dry
surfaces, such as landing nets or dry hands, its mucous layers
commonly called slime layers may be partially removed, presenting
an opportunity for bacteria or pathogens to invade the skin.
Burping and Puncturing
When certain fish are brought
up from depths greater than 40 feet too quickly, their swim bladders,
which normally control buoyancy, can overinflate from rapid depressurization.
Burping is a technique used on a fish with an overinflated swim bladder.
The fish is massaged in the belly region in an attempt to release the
excess air in the swim bladder. Puncturing involves using a needle or
ice pick to poke a hole in the fish's exposed swim bladder. Both
of these techniques are currently being advocated in other parts of the
country. However, if the procedure is not carried out correctly, more
damage than good may be done to the fish.
The success of burping depends
on the species of fish. Some fish, such as largemouth bass, perch, striped
bass, cod, hake, and black sea bass, do not have a connection from their
gut to their swim bladder. If a fish's gut is not connected to its
swim bladder, then burping is impossible. Puncturing is a very controversial
technique. To date, there is no evidence that puncturing will increase
a fish's chance of survival.
The best advice for releasing
fish with overinflated swim bladders is to let them go as quickly as possible.
NEVER ATTEMPT TO BURP
OR PUNCTURE A FISH WITHOUT KNOWING WHAT TO DO!
These guidelines provide basic
information on the most beneficial catch-and-release methods for most
small- to medium-sized freshwater and marine fish:
- If you plan to fish with
artificial lures, such as plugs and spoons, consider replacing treble
hooks with single hooks. Single hooks are quicker and easier to remove,
especially when dealing with such predatory fish as bluefish and northern
pike. Consider pinching the barb on your hooks, since this will make
releasing the fish much easier.
- Plan your release strategy.
Decide whether to keep or release any fish prior to angling or at least
before removing the fish from the water. Familiarize yourself with any
regulations in effect for the species targeted, and gather any items
that will facilitate handling and releasing the fish.
- When a fish is hooked, use
a steady, deliberate retrieval technique. This can reduce the amount
of stress a hooked fish undergoes when pulled up from the depths too
quickly, or when physically exhausted from an overly slow retrieve.
- Once you have decided on
releasing the fish, avoid netting or even removing it from the water
if possible. Use needle-nosed pliers to pry the hook from the fish while
it is still in the water. Fish that can be lifted by the leader
the short length of line used to attach the end of the fishing line
to the lure or hook can easily be released over the rail using
a "dehooker." These devices, whether homemade or purchased,
are gaining in popularity in the bluefish industry to avoid the
fish's nasty teeth and are useful for releasing a number
of other species. A dehooker may simply be a metal rod with a handle
at one end and a small upturned hook at the other end. If live bait
or a lure is deeply embedded in the fish's gullet, cut the leader
close to the fish's mouth and let the fish keep the hook. Studies
have shown that fish can get rid of the hook up to 120 days later.
- When landing the fish, it
is important to minimize out-of-water time and any fish contact with
surrounding surfaces or objects.
moistened. This helps prevent removal of the fish's natural
protective mucous layer, and reduces the chance of subsequent infections
in the fish's skin.
handling, particularly of the gills and soft underbelly. Gently
prevent the fish from battering itself on surrounding hard surfaces.
Place the fish on an old piece of foam cushion and place a wet rag
or gloved hand over the fish's eye. These two actions can do
much to subdue even unruly tuna and bluefish.
- Return the fish to the water
headfirst. In most cases, it is best to point the fish's head straight
down and allow the fish to plunge down into the water.
Klauber, A. 1992. Catch &
Release. In: Nor'easter: Magazine of the Northeast Sea Grant Programs.
Malchoff, M.H., M.P. Voiland,
and D.B. MacNeill. 1992. Guidelines to Increase Survival of Recreational
Sport Fish. Cornell Cooperative Extension Fact Sheet.