Sight-Fishing the Spawners

Easy Catch or Cause for Concern

 

By Scott Bryan

Arizona Game and Fish Department

Research Branch

 

It’s one of those beautiful spring mornings in Arizona.  Temperature is just right, sun is shining bright.  Fishing reports say that the largemouth bass are hitting anything thrown in their direction.  It’s a perfect time to cruise the shorelines and find those bass beds.

 

The sun is producing quite a glare, but my polarized sunglasses allow me to easily see 15 feet into the water.  There he is.  Must be a 3-4 pounder.  I can see him plain as day, sitting in his saucer shaped nest in about 6 feet of water.  I throw an 1/8th ounce chartreuse jig just past the bed, a few cranks of the reel and I let it fall right next to him.  The fluttering action drives him crazy and he strikes.  Now the fight is on, this one is better than I thought.  He fights pretty good for about 60 seconds, then I play him for another 60.  He’s tired now, can’t even get himself upright as I bring him closer to the boat.  My partner nets the 5 pound male and we snap a few pictures, release him and watch him slowly return to the nest.  Looks like the start of a great day.

 

Or have I just done my part to reduce the bass population in my favorite lake?

 

It seems that sight-fishing for spawning bass has become quite a popular activity in Arizona lakes.  After all, you are almost guaranteed to catch fish, so it’s a great time to take out the kids for some fishing fun, observe how the action of your new lure elicits a strike from a bass, or join in on one of the hundreds of bass tournaments held throughout the spring.  But have you stopped to think about how your fishing fun may affect the reproductive success of your beloved game fish?

 

It seems that many researchers have pondered this very question.  I took some time to summarize the findings of several of these studies below.

 

First, a reminder of the facts that we all know.  Male black bass (largemouth, smallmouth, and spotted) build solitary, shallow and highly visible, saucer-shaped nests in the substrate and court and spawn with females.  After fertilization, the male bass fans the eggs in those nests until they hatch (for oxygenation) and then guards the newly hatched fry against predators until they have grown to independence; typically about 6 weeks after fertilization.  It is this time of parental care that male bass are particularly vulnerable to our sight-fishing techniques.  You see, when on the nest, the male does not eat and he is certainly not “stupid” (as some anglers suggest), but he will vigorously defend the nest from intruders (including our lures) at any cost.  When removed from the nest, even for short periods, predators can, and will, quickly consume the offspring.  The level of predation is directly proportional to the time the fish is absent from the nest, but if the male is harvested, the offspring have no protection and have almost no chance of survival. 

 

So, anglers often assume that as long as the fish is released immediately, they will return to the nest, right?  Well, that’s partially correct.  A study conducted just two years ago suggests that behavioral and physiological effects of catch-and-release angling can significantly reduce reproductive success.  Here’s what they did.  Researchers used high-tech underwater cameras and ultra-sensitive telemetry equipment to determine the impacts of catch-and-release angling on nesting bass.  The study was conducted on a lake in Ontario, Canada in which the researchers angled for tagged fish (both nesting and non-nesting).  When caught, fish were played for 150 seconds, then held out of the water for 30 seconds, and returned.  Following release, all of the nesting fish immediately swam past the nest into deeper water, but then returned within 3 minutes.  So yes, they did return the nests.  But in what condition?  The researchers found that the nesting fish returned to only 63% of their pre-angled strength even after 24 hours of recovery.  During this time, they had lost their energy source used for short-burst activities, such as chasing away predators.  So in effect, even though the male bass was still technically guarding the nest, he did not have the energy stores necessary to effectively ward off predators.  In contrast, non-nesting fish fully recovered within one hour.  The conclusion: catch-and-release angling caused a significant amount of physical impairment for over 24 hours after release and the male was unable to effectively defend the nest during that period.  This was directly related to a decrease in reproductive success and ultimately resulted in a reduced bass population.

 

Other studies have taken this information a step further to determine if reducing the time it takes to land a fish will increase the fishes ability to return to the nest and successfully defend it.  They found that increased angling time means a higher depletion of energy stores and results in a decreased ability to guard the nest.  In fact, fish played to exhaustion took 4 times longer to return to the nest than fish played briefly.  Also, if a male returns to a smaller brood, meaning that a predator has removed a portion of the fry, the bass will typically abandon the nest.  This is important because female bass target the larger males (as do anglers), so the larger bass are guarding more offspring.  If that large male is removed, it has more of an impact than if a smaller bass were removed.  Other researchers have found that the abandonment rate increased with increased number of times a fish was caught.

 

Finally, there has been some question as to the effect of bass tournaments on spawning fish.  It seems that the number of tournaments increases significantly during the spring and they might be having some impacts on the nesting fish.  Typically, tournament anglers begin fishing early in the morning and fish throughout the day.  At a specified time, anglers bring all of their fish to a specified location for weighing and then the fish are released immediately.  Of course, all the above applies, when fish are taken off their beds, the predators will move in.  Some interesting results from studies conducted in the last 5 years suggest that bass will never go back to their nests and they typically won’t ever return to the area where they were caught.  In fact, in weigh-in tournaments, fish move only about 0.2 miles from their release site within 24 hours; 0.3 miles over the next two weeks; 0.8 miles in the first 46 days; and only 1.3 miles after 75 days.  Fish showed no homing tendency even after 221 days of the tournament.  In addition, fish that were culled reacted in the same manner.  Because of this, many astute anglers concentrate their fishing efforts in areas of tournament releases which in turn increases the harvest rate of these fish.  

 

So do we stop fishing for the spawners?  Some states and provinces have gone to closed seasons or closed areas during the spawning period.  One study found a 20% increase in reproductive success in the closed area compared to the open area.  Is this what should happen in Arizona?  In some areas it already does.  For example, the Agua Fria arm of Lake Pleasant is closed during the entire spawning season for bald eagles.  However, reproductive success of bass has not been evaluated and compared to open fishing areas in that lake.  It may be an area for future research.  However, we appear to have good reproductive success in most of our lakes, but it could be better.  Responsible angling practices will go a long way in ensuring the success of our bass populations in the future.  Here are some suggestions:

 

·        Fish should not be played for long periods of time, try to land the fish within 30 seconds to minimize disturbance. 

·        Limit air exposure to reduce stress and allow the fish to return to the nest in a shorter time.  If you want to get a picture, be ready to snap it quickly!

·        Release the fish as near to the nest as possible; increasing the release distance increases the amount of time to return to the nest.

·        Do not catch the same fish repeatedly, this will lead to higher rates of abandonment.

·        Try paper tournaments instead of weigh-in tournaments

·        Release fish from tournaments in various locations for better distribution.

 

Sight fishing for spawners is a matter of personal choice.  In my research of this topic, all studies that I found concluded that taking bass from their beds was harmful to reproductive success.  But each of the studies suggests that anglers can limit the impact by practicing responsible catch-and-release techniques. 

 

Good luck out there, and remember that your actions today will ensure successful bass fishing in the future.