Movement, home range and habitat selection of stocked juvenile muskellunge, Esox masquinongy, in Forbes Lake, Illinois: exploring the effects of latitudinal origin

Abstract

Intraspecific, seasonal and diel variation in movement behaviours of three stocks of juvenile (age-2; 399-610 mm total length) muskellunge, Esox masquinongy Mitchill, were assessed using radio telemetry in Forbes Lake (225 ha), IL, USA. Experimental populations included muskellunge from the Upper Mississippi (Leech Lake, MN, USA) and Ohio (Cave Run Lake, KY, USA) river drainages, as well as progeny from North Spring Lake, IL, a mixed-origin stock. No differences in hourly movement rates or home ranges were detected among stocks. Movement rates were greatest during spring (mean ± SE = 42 ± 4 m h )1 ), lowest during summer (16 ± 3 m h )1 ) and intermediate in autumn (28 ± 5 m h )1 ). Additionally, movement rates during the summer were greater at night than crepuscular periods. Home range sizes were similar during spring and autumn (mean ± SE = 17-18 ± 3-4 ha) and decreased during summer (5 ± 3 ha). Although habitat selection characteristics were generally similar among stocks, fish from the Upper Mississippi River drainage occupied deeper water more frequently and selected the pelagic zone more strongly during the spring than those from the Ohio River and mixed-origin stocks. Within the littoral zone, muskellunge selected coarse woody habitat and aquatic macrophytes. Collectively, these findings suggest little behavioural differentiation among genetically divergent stocks when evaluated in a common reservoir environment. K E Y W O R D S : behaviour, intraspecific variation, muskellunge introductions, stocking program, stocks, telemetry.

Structural Complexity Influences Littoral Coarse Woody Habitat Selection by Juvenile Muskellunge

“…Habitat selection and availability.-Juvenile Muskellunge (age-2; 485 § 70 mm total length, mean § SD) were surgically implanted with radio-transmitters and introduced into Forbes Lake to evaluate movement, home range, and habitat selection (Wagner and Wahl 2011). All Muskellunge were progeny of wild parental fish from three stocks (Upper Mississippi River drainage stock, Ohio River drainage stock, and North Spring Lake, Illinois [this last a mixed-origin brood stock]; Wahl 2007, 2011).…”

“…Muskellunge were reared in earthen ponds in close proximity to source locations and were acquired as age-0 advanced fingerlings in fall 2002, at which point they were held in a common pond environment near Forbes Lake until implantation and stocking in March 2004 at age 2 Wahl 2007, 2011). Previous analyses of these telemetry data (Wagner and Wahl 2011) focused on potential differences among genetically divergent stocks with only a limited examination of general habitat selection and did not include a detailed examination of selection for CWH complexity.…”

“…Transmitters were intraperitoneally implanted lake-side using established surgical procedures, and manual tracking was conducted by boat from March to December 2004 (Wagner and Wahl 2007Wahl , 2011. All fish were located at least once every 2 weeks.…”

“…All Muskellunge locations were classified as littoral or pelagic, with the littoral zone defined as the area from the shoreline to the 2-m depth contour, which was generally the maximum depth of macrophytes growth (Wagner and Wahl 2011). Muskellunge primarily occupied the littoral zone during the summer (63% of all locations from 15 June to 14 September; Wagner and Wahl 2011).…”

“…Due to loss of habitat, natural recruitment of Muskellunge does not occur in many systems, and populations are maintained entirely through stocking (Wahl 1999). Muskellunge frequently use littoral CWH throughout the year (Hanson and Margenau 1992;Newbrey et al 2005;Wagner and Wahl 2011), and CWH in these systems may provide stocked Muskellunge refuge from predation and enhanced foraging opportunities, which may increase survival rates (Szendrey and Wahl 1996). However, how CWH complexity influences Muskellunge habitat use is unknown.…”