A "NO FISH DRY JULY" TO MINIMIZE RELEASE MORTALITY

 

This is one of those essays that shouldn’t have to be written.

We all know that fish live in water.  We know that fish breathe the oxygen dissolved in that water, and that with the exception of a handful of species typically native to still, hot, tropical rivers, fish are incapable of breathing air.  But it doesn’t take more than a few seconds of perusing folks’ social media accounts to find far too many anglers forgetting that fact, as they hold their gasping, slowly dying catch in their hands and pose in front of a lens.

While some species can tolerate that sort of handling, particularly when air temperatures are fairly low, others are extremely sensitive to any sort of handling.  Even relatively tolerant species become vulnerable when air temperatures rise.

Posing with a fish on a hot summer day is one of the best ways to increase the release mortality rate.

Thus, a group of conservation-minded anglers who have come together under the banner of the organization Keep Fish Wet have come up with their newest campaign, which promotes “No Fish Dry July,” which is described as

“an initiative to help anglers create better outcomes for each fish they release.  For the month of July, Keep Fish Wet and Ten and Two Co. challenge you to make a 31-day commitment to not take a single photo of a fish.

“…Instead, we encourage you to post other artful shots of your summer angling experience.  This simple shift in the angling community’s catch-and-release behavior could do years of good for your fish’s home water.”

The Keep Fish Wet webpage tends to focus on trout, although its message has wider application.  It states that

“In general, for every 10 degrees Celsius increase in water temperature, a fish’s metabolic rate doubles.  This means that at warmer water temperatures, fish have a higher metabolism and need more food.  It also means that at warmer water temperatures fish need more oxygen, a critical component of the metabolic process.  However, remember that, all else being equal, warmer water holds less oxygen than cooler water.

“As fish exercise, like on the end of a fishing line, their metabolism increases, as does their need to bring more [dissolved oxygen] into their bodies.  If water temperatures are high and [dissolved oxygen] is low, then fish need to work extra hard to recover from angling stress, and in extreme cases, they perish.”

That statement is as true for striped bass and bluefish as it is for trout and salmon.

More than two decades ago, the State of Maryland conducted extensive research on recreational striped bass release mortality.  It found that air temperature, as well as water temperature, affected the survival of released striped bass.

“A profound effect on shallow hooking mortality [as distinguished from deep “gut hooking,” which was the single most reliable predictor of death] was documented in relation to air temperature.  When air temperatures were below 95F, the mortality of shallow hooked striped bass, those fish only stressed by physical exertion not by lethal hook wounds, was 0.8%.  When air temperatures ranged from 95F to 105F in July, mortality rose to 17.2%.  The mortality rate of all shallow hooked fish combined was 3.5% for the entire study period.”

The Maryland study found that 95% of the bass that succumb to release mortality do so within 24 hours after release.  However, such death is generally not immediate.  Thus, as Keep Fish Wet notes,

“just because you watched the fish swim away does not mean it will be fine.”

So how can anglers spot fish at risk of succumbing to release mortality?  There are a number of reliable signs.  They generally fall into the categories of escape response, righting response, regular ventilation, and eye tracking.

Escape response is easy to check.  At the end of the fight, just reach over and grab the fish by tail, right ahead of the fin.  If the fish responds, and struggles to get away, it is healthy and likely to survive release.  If it seems indifferent to being restrained, it may not survive release.

Righting response is equally obvious.  Fish typically swim with their backs toward the surface of the water, and their bellies toward the bottom.  Tired fish often slump over on their sides, or even turn upside-down at the end of the fight.  If an upside-down fish can’t right itself within five seconds, it is a strong candidate for release mortality.

Regular ventilation merely means that a fish is opening and closing its gills at regular intervals.  If a fish is incapable of doing that—effectively, if it is having difficulty breathing—death probably isn’t too far away.

Eye tracking, the final criteria, is a little more difficult to gauge.  The fish must be placed in the water, then rolled gently from side to side.  If its eyes remain level, and move to compensate for its body’s movement, the fish is deemed to have a better chance of survival than it would if the eyes just glassily stared out from their sockets, and showed no movement at all.  If the latter occurs, the fish is very likely to die.

Fish that show positive escape or righting responses may be safely released; those that fail both tests have substantially impaired chances of survival.  One study suggests that bonefish which fail to show a strong righting response are six times more likely to be attacked and killed by predators, probably within 20 minutes of release.  Notably, the study also found that

“Longer air exposure and overall handling times were significant predictors of the loss of equilibrium in angled bonefish.”

Of course, longer air exposure and longer handling times are exactly what results when fish are kept out of the water for photos, instead of being quickly returned or, even better, released without removing them from the water at all.

The next question that arises is what ought to be done with fish that fail the righting response test.  Anglers typically hold such fish beneath the water’s surface, trying to force water over their gills by moving them back and forth, but it’s not clear that such actions do very much good.  Keep Fish Wet suggests that any such fish, even if they subsequently meet the regular ventilation and eye tracking standards, be held in a net or live well until they recover enough to make survival likely.

While that may be possible for some species and some anglers, it is extremely impractical for others.  No matter how good their intentions, anglers can’t legally toss an exhausted striped bass into their boat’s live well until it begins to recover, if they already have a striped bass in the cooler; doing so would constitute a violation of the 1-fish bag limit.  For similar reasons, anglers can’t retain an under- or over-slot bass, or a fish caught outside the season for legal retention, without violating the law.

There are also physical limitations.  While putting a fish in a live well sounds good on paper, it assumes that the angler’s boat contains such a holding device.  Many don’t, either because the boat is too small or because the boat came without that particular amenity.  When I had my current boat built, I opted against having a live well included, since I don’t normally liveline baits, and had better use for the space that I live well would have occupied.

Shore-based anglers, under most circumstances, also lack access to a live well, and so cannot use one to nurse exhausted fish back to health prior to release.

The most practical option, then, is not to exhaust the fish in the first place.  Exhaustion attributed to the fight can be minimized by using heavy tackle; exhaustion attributed to the release is best avoided by releasing the fish in the water whenever possible and, as the No Fish Dry July campaign suggests, by minimizing the time fish spend out of the water by eschewing cameras and relying on memories to record the experience.

Having said that, will I be completely abandoning my cameras this summer?

Absolutely not.  I’ll continue to record the release of big fish—probably mostly sharks, but other pelagic species can’t be wholly discounted—that are never removed from the water, but are unhooked and set free while water flowed over their gills.  And I’ll photograph fish such as dolphin (mahi-mahi), black sea bass, and the occasional tuna, which are caught and retained for food, making the release mortality issue irrelevant.

There is no reason why other folks shouldn't do the same.

But for fish intended for release, the no-photograph pledge is a very, very good idea.