Seasonal Movements and Distribution of Steller’s Eiders (Polysticta stelleri) Wintering at Kodiak Island, Alaska

ARCTIC ◽  
2014 ◽  
Vol 67 (3) ◽  
pp. 347 ◽  
Author(s):  
Daniel H. Rosenberg ◽  
Michael J. Petrula ◽  
Jason L. Schamber ◽  
Denny Zwiefelhofer ◽  
Tuula E. Hollmén ◽  
...  
2017 ◽  
Vol 573 ◽  
pp. 203-213 ◽  
Author(s):  
BJ Lyon ◽  
RG Dwyer ◽  
RD Pillans ◽  
HA Campbell ◽  
CE Franklin

1991 ◽  
Vol 6 (3) ◽  
pp. 305-313 ◽  
Author(s):  
Carl W. Prophet ◽  
Thomas B. Brungardt ◽  
N. Kay Prophet

1983 ◽  
Vol 10 (3) ◽  
pp. 639 ◽  
Author(s):  
GJW Webb ◽  
SC Manolis ◽  
GC .Sack

A 52.5-km section of the Adelaide River, N.T. (12�13'S., 131�13'E.). was spotlight-surveyed 20 times between June 1979 and September 1981. C, johnstoni (15.3 � 9.2 sighted per survey) were less abundant than C. porosus (137.6 � 36.5 sighted per survey), and were mainly in the upstream 20 km of the survey route (96% of C. johnstoni sightings); here considered a zone of syntopy within the survey route. C. johnstoni congregate in the main stream during the dry season and disperse from it during the wet season, which parallels similar seasonal movements to and from dry-season refuges in non-tidal areas lacking C. porosus. As the dry season progresses, C. johnstoni are located further and further upstream, and this movement (or loss ofanimals) appears unrelated to changes in salinity. Numbers of C.johnstoni within the zone of syntopy are negatively correlated with numbers of C. porosus (r*2 = 0.50, P=0.005). and competitive exclusion may be occurring. Independent of seasonal factors, numbers of C. johnstoni within the zone of syntopy declined with consecutive month (1979-81: r*2=0.47, P= O.004), whereas numbers ofthe more recently protected C, porosus increased (r2 = 0.48, P= 0,006). The location of the syntopic zone was unchanged.


2002 ◽  
Vol 59 (3) ◽  
pp. 405-415 ◽  
Author(s):  
P Apostolaki ◽  
E J Milner-Gulland ◽  
M K McAllister ◽  
G P Kirkwood

We present a model of the effects of a marine reserve on spawning stock biomass (SSB) and short- and long-term yield for a size-structured species that exhibits seasonal movements. The model considers the effects of protecting nursery and (or) spawning grounds under a range of fishing mortalities and fish mobility rates. We consider two extremes of effort redistribution following reserve establishment and analyze the effects of a reserve when the fishery targets either mature or immature fish. We apply the model to the Mediterranean hake (Merluccius merluccius) and show that a marine reserve could be highly beneficial for this species. We demonstrate benefits from reserves not just for overexploited stocks of low-mobility species, but also (to a lesser extent) for underexploited stocks and high-mobility species. Greatly increased resilience to overfishing is also found in the majority of cases. We show that a reserve provides benefits additional to those obtained from simple effort control. Benefits from reserves depend to a major extent on the amount of effort redistribution following reserve establishment and on fishing selectivity; hence, these factors should be key components of any evaluation of reserve effectiveness.


1965 ◽  
Vol 55 (1) ◽  
pp. 59-63
Author(s):  
John Northrop

Abstract A large T-phase signal was received at Pt. Sur, California, from the Alaskan earthquake of March 28, 1964. Additional T phases were received from 90 per cent of the 80 aftershocks studied in the Kodiak Island area. The largest T phases were received from hypocenters beneath the upper portion of the continental shelf.


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