Hoff: A nursery site of Bathyra/a parmifera in the eastern Bering Sea 
243 
Habitat requirements of newly hatched juvenile 
skates may not be the criteria for nursery-site selec- 
tion because very few newly hatched skates were found 
at the site. The most likely explanation is that neo- 
nate skates move out of the nursery area shortly after 
emergence, possibly to reduce intraspecific competition 
along the slope edge or to avoid large predators that 
prey on juvenile skates (Hoff, 2007). In trawl studies 
with the same designs and methods as those of the 
present study and conducted across the outer conti- 
nental shelf region, newly hatched juvenile Alaska 
skates were found to be common (Kotwicki and Wein- 
berg, 2005; Lauth and Acuna, 2007). Many individu- 
als encountered on the outer shelf still possessed tail 
filaments, providing evidence of recent emergence from 
the egg case (Hoff, 2007). The reason why juvenile 
skate move to inner and outer shelf waters remains 
unclear; however, a pattern in their movements from 
inner to outer shelf regions in the eastern Bering Sea 
and in their use of different habitats at different life 
stages is evident. 
These patterns indicate that skate nurseries may be 
occupied by skates at two of most critical life stages 
(embryos and adults), and conservation efforts tar- 
geting these stages may have the greatest impact on 
population protection (Frisk et al., 2002, 2004). Skate 
nurseries in general may be located in areas of high 
biological productivity and therefore are susceptible to 
disturbances caused by increased fishing activities. As 
oviparous elasmobranch fishing mortality increases, 
recognition and protection of nursery habitats may be 
one approach to ensure healthy populations. Likewise, 
nursery sites may become important locations to be 
monitored for the health and recruitment potential of 
skate species. Long-term monitoring of these impor- 
tant habitats can provide a wealth of information with 
minimal effort because of the permanence or long-term 
stability of these nursery sites. 
Acknowledgments 
I thank the skippers and crew of the FVs Ocean Explorer, 
Sea Storm, Nordic Fury, Arcturus, Aldebaran, and Great 
Pacific. I especially thank D. Stevenson, S. Kotwicki, 
S. Gaichas, R. Reuter, E. Iwamoto, E. Acuna, E. Jor- 
genson, C. Gredzens, B. Voss, B. Lauth, R. Nelson, G. 
Stauffer, and G. Walters for their support. I also thank 
T. Essington, D. Gunderson, D. Kimura, T. Pietsch, and 
C. Rooper for their review and helpful suggestions to 
improve this manuscript. This project was supported 
by North Pacific Research Board (NPRB grant no. 415), 
Essential Fish Habitat (EFH), and the Alaska Fisheries 
Science Center. 
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