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Tracking studies for invasive lionfish ( Pterois volitans and P. miles ) in the Western Atlantic can provide key information on habitat use to inform population control, but to date have likely underestimated home range size and movement due to constrained spatial and temporal scales. We tracked 35 acoustically tagged lionfish for >1 yr (March 2018-May 2019) within a 35 km 2 acoustic array in Buck Island Reef National Monument, St. Croix, US Virgin Islands (an area 10× larger than previous studies). Tracking lionfish at this scale revealed that home range size is 3-20 times larger than previously estimated and varies more than 8-fold across individuals (~48000-379000 m 2 ; average: 101000 m 2 ), with estimates insensitive to assumptions about potential mortality for low-movement individuals. Lionfish move far greater distances than previously reported, with 37% of fish traveling >1 km from the initial tagging site toward deeper habitats, and 1 individual moving ~10 km during a 10 d period. Movement rates, home range size, and maximum distance traveled were not related to lionfish size (18-35 cm total length) or lunar phase. Lionfish movement was lowest at night and greatest during crepuscular periods, with fish acceleration (m s -2 ) increasing with water temperature during these times. Our results help reconcile observed patterns of rapid recolonization following lionfish removal, and suggest complex drivers likely result in highly variable patterns of movement for similarly sized fish occupying the same habitat. Culling areas ≥ the average lionfish home range size identified here (i.e. ~10 ha) or habitat patches isolated by ≥ ~180 m (radius of average home range) may minimize subsequent recolonization. If the shallow-deep long-distance movements observed here are unidirectional, mesophotic habitats may require culling at relatively greater frequencies to counteract ongoing migration.
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This content will become publicly available on January 16, 2026
Seasonal changes in the movements rates and activity patterns of Canada lynx
In Subarctic and Arctic environments, daily patterns of activity and space-use are strongly influenced by interplay between seasonal abiotic factors and the corresponding responses of the biotic environment. Here we combined accelerometry with GPS telemetry of Canada lynx (Lynx canadensis (Kerr, 1792), n=12) in northern Alaska to test the hypotheses that lynx activity would peak during twilight throughout the year, coinciding with activity of their preferred prey, and that individuals with larger home ranges would have greater spatial displacement and expend more energy on movement. Lynx activity occurred throughout the 24h day and peaked during twilight, but variation among individuals was high and diel rhythms were sometimes only detectable using the finer resolution accelerometer data. Surprisingly, home range size was not correlated with movement costs estimated via acceleration, but step length and acceleration were correlated in a positive curvilinear fashion. However, step length was sometimes disproportionately lower than predicted by acceleration. Such intervals of high activity with low spatial displacement were often followed by periods of rest, suggesting they may be indicative of hunting in a restricted patch of habitat. We conclude that accelerometers can provide additional information to supplement GPS data, providing a more complete picture of animal behavior.
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- Award ID(s):
- 2224776
- PAR ID:
- 10571096
- Publisher / Repository:
- Canadian Science Publishing
- Date Published:
- Journal Name:
- Canadian Journal of Zoology
- ISSN:
- 0008-4301
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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