Where Do Tournament-Released Bass Go?

For displacement studies, these two waters reduce the problem of identifying bass that likely are familiar with the way home from those that don’t know where they are. Bass with home ranges in Lake Wawasee would less likely be familiar with Lake Syracuse, and vice versa, compared to bass in waters like Chesapeake Bay and the Potomac River, which offer no separation beyond distance.

Pearson put ultrasonic transmitters in 10 adult largemouth bass, 15 to 20 inches in length, captured in Lake Wawasee by electrofishing and angling. Five were displaced downstream into Syracuse Lake; two were displaced within Lake Wawasee; and two were released at their capture sites.

Only one bass from Wawasee that was taken to Syracuse Lake returned. That fish remained in Syracuse Lake for 11 days, explored the channel, and moved into Wawasee on the 18th day. It was then tracked within a home range in northern Lake Wawasee for another 330 days near the site where it was originally captured. This location and behavior suggests that this bass may have been more familiar with part of the channel and marshes connecting the two lakes than the other displaced bass, which had been captured farther south.

Another bass displaced from Lake Wawasee to Syracuse Lake entered the channel between the lakes but stayed mainly in Lake Syracuse until it was caught by an angler 21 days after release. A third bass died or shed its transmitter after 28 days of wandering around Syracuse Lake. The other two bass taken to an unfamiliar lake swam about Lake Syracuse for 11 and 46 days, without any apparent attempt to return to Lake Wawasee through the channel.

Two bass displaced within Lake Wawasee returned to their capture areas and were subsequently monitored for 337 and 456 days, respectively. And two bass released at their capture sites stayed in nearby home ranges for 77 and 450 days, respectively. The five displaced fish were tracked an average of 91 days, compared to an average of 329 days for the four fish left in (presumably) more familiar territory.

The only displaced fish that was tracked longer than 46 days after release was the one that was able to move back to its home area. It would require a larger study to verify, but it appears that displacement to unfamiliar territory reduces the ability of bass to cope and survive. Wandering or lost bass may be more vulnerable to anglers, perhaps because they’re less able to capture adequate prey and are active longer.

The rate of return of displaced bass in Pearson’s study is similar to or lower than the rates in other bass tracking studies in which about 50 percent or fewer bass returned home when moved more than 10 miles from their capture sites.

Other observations by Pearson are relevant. Largemouth bass in Lake Wawasee didn’t seek deeper water during winter, but occupied the same offshore areas they used during summer and fall. Some of the fish also moved shallower into ice-covered canals used for spawning in spring. The home ranges of tagged bass were large compared to home ranges measured in other tracking studies. Perhaps a relatively low forage base in Wawasee forces bass to hunt longer and cover more area?

Angler-Tag Study

In a related study on the same lakes, Pearson attached anchor tags to 24 largemouths caught in an April tournament from unknown locations, and to 12 other bass collected by electrofishing in southeast Lake Wawasee. He released them all in Lake Syracuse. Tag returns suggested that displaced bass did not readily return to Lake Wawasee and that displaced fish are more vulnerable to anglers. At least 9 of the 36 tagged bass displaced to Syracuse Lake were later caught by anglers. One was recaptured twice. None were recaptured in Lake Wawasee, but one left Syracuse Lake and moved downstream before recapture.