Biologist reports logo Radio Telemetry Update

Susquehanna and Bradford Counties
Spring 2005

Thanks in part to a grant from the FishAmerica Foundation, Area 4 biologists monitored the movement of preseason stocked trout with the use of radio telemetry in two streams this spring. Click here to view details on the radio telemetry procedure. The two study waters we used were Wysox Creek in Bradford County and Tunkhannock Creek in Susquehanna County. We placed 12 radio-tagged trout in Wysox Creek. These were four rainbows, four browns, and four brooks. We placed 13 radio-tagged trout in Tunkhannock Creek. These were five rainbows, four browns, and four brooks.

The radio-tagged fish showed little movement for the first three days of the study. Then, between day 4 and day 6, all of the rainbows in Wysox Creek and four of the five rainbows in Tunkhannock Creek left their stocking points. We never found three of the Wysox rainbows again. We found the fourth on day 16. It was in the North Branch Susquehanna River between Catawissa and Danville, 123.1 miles away from where we stocked it. The Tunkhannock Creek rainbows were easier to monitor and we only lost track of one of these fish. With a single exception, the Tunkhannock rainbows dispersed downstream from the lower stocking limit. The lone exception was a rainbow we stocked near the town of Smiley. This fish stayed at its stocking point for 14 days before taking up a position in a deep pool 0.4 miles downstream. Once they took up a position, most of the Tunkhannock rainbows remained in that vicinity for the rest of the study. The farthest downstream movement we documented for the Tunkhannock rainbows was 12.6 miles. This fish found a home in a side channel near the confluence with Field Brook. It remained in the side channel until dropping water levels forced it back into the main stream on April 12.

Tracking trout along Wysox Creek
Tracking trout along Wysox Creek

Brown movement was more variable than rainbow trout movement. Some of the brown trout moved between day 1 and day 2, but most of them stayed at their stocking points for at least seven days. Brown trout movement was generally downstream but one Wysox brown moved 0.7 miles upstream. One Tunkhannock brown moved a total of 6.3 miles but the others didn’t travel as far. These fish moved between 0.3 and 2.6 miles downstream. Only one of the brown trout found its way into the river. This fish took up a position in the river near the mouth of Wysox Creek and then traveled back and forth between the river’s banks. We lost track of two brown trout during the course of the study.

Brook trout stayed at their stocking points for the longest time. With one exception, the brook trout remained in place for a minimum of 10 days. The lone exception was a Tunkhannock Creek fish that began moving after 7 days. Brook trout movement ranged between 0.5 and 11.6 miles with the greatest movement occurring in Tunkhannock Creek. One Tunkhannock brookie moved about 7.5 miles downstream before ascending Nine Partners Creek to its confluence with Butler Creek. This was the only time during the entire study that we documented a fish entering a tributary stream. We lost track of one Wysox brook trout after 17 days and believe two others were preyed on by a mink.

By the end of the preseason period, 3 of the 12 radio-tagged trout (two browns and a brook) remained within the stocking limits of Wysox Creek and 3 of the 13 radio-tagged trout (two browns and a rainbow) remained within the stocking limits of Tunkhannock Creek.

Tunkhannock Creek Flooding
Tunkhannock Creek Flooding

Data analysis will continue into this winter and hopefully will give us some insights into why the fish move. For now, we can say that water chemistry and flooding are probably not factors on the two study waters. The worst pH we found during the entire preseason period was 6.8 following heavy rains and snowmelt. During the two floods we experienced this spring, the radio-tagged trout did not move. We may gain further insight into preseason movement from angler tag returns. We remind anglers that almost all of the preseason trout we stocked in these waters were tagged. If you catch a tagged fish, please report it to rwnuk@pa.gov.

 
-- Rob Wnuk, Area 4

Biologist Reports -- PFBC Home


Copyright Notice
Commonwealth of Pennsylvania Web Privacy and Security Policies