Long-term movements of tiger sharks satellite-tagged in Shark Bay, Western Australia

2007 ◽  
Vol 151 (4) ◽  
pp. 1455-1461 ◽  
Author(s):  
Michael R. Heithaus ◽  
Aaron J. Wirsing ◽  
Lawrence M. Dill ◽  
Linda I. Heithaus
Keyword(s):  
2003 ◽  
Vol 54 (8) ◽  
pp. 913 ◽  
Author(s):  
M. Moran ◽  
C. Burton ◽  
J. Jenke

Snapper is an important commercial and recreational target species in the Shark Bay region of Western Australia. The present study aimed to define the range of movements of snapper by tagging in the two inner gulfs of Shark Bay and on oceanic fishing grounds adjacent to the Bay. Recaptures by fishers fell to low levels within 4 years after tagging, but small numbers of recaptures were still being made up to 15 years after release. There was no mixing of snapper populations between the two inner gulfs nor was there any movement between the ocean and the inner bay. This supports genetic and other evidence for the existence of several separate stocks in the region. Snapper of the ocean stock were mostly recaptured within 20 km of their release point, although a few fish moved long distances of up to 370 km southwards along the continental shelf. The tagged snapper tended to become more dispersed along the shelf with increasing years at liberty. Yet, an empirical model indicated that of the snapper recruiting to the main oceanic fishing grounds near Koks Island, which have a mean life expectancy in the fishery of 1.5 years, 76% would remain within 93 km (50 nautical miles), even after 6 years. The distinct stocks and their movement characteristics are significant for snapper fishery management in the Shark Bay region.


2012 ◽  
Vol 63 (11) ◽  
pp. 1129 ◽  
Author(s):  
B. S. Wise ◽  
C. F. Telfer ◽  
E. K. M. Lai ◽  
N. G. Hall ◽  
G. Jackson

Effective management of a recreational fishery must include long-term monitoring programs that allow determination of trends in temporal and spatial variability of catch and effort data. Such monitoring becomes of inherently greater importance when managing a recreational fishery in a World Heritage Area, such as Shark Bay, Western Australia. Between 1998 and 2010, 11 12-month bus-route surveys of boat-based recreational fishing were undertaken at three key boat ramps in Shark Bay. These surveys demonstrated that, in response to the progressive implementation of new management measures, the estimated annual recreational fishing-boat effort decreased by 46%. As a consequence, the estimated annual retained and released catches of the key species, pink snapper (Pagrus auratus), declined and the proportions of the catches of this species that were released each year increased. Annual catches of other species also declined, however, the composition of species retained and released each year varied. The study demonstrated that monitoring of the recreational fishery within Shark Bay provided both immediate and longer-term data on the responses by recreational fishers to changes in management. This produced the information necessary to assess the effectiveness of management measures that were introduced and to modify these as required.


2016 ◽  
Vol 22 (2) ◽  
pp. 105-122 ◽  
Author(s):  
Patrick W. M. Corbett ◽  
Rayana Estrella ◽  
Andrea Morales Rodriguez ◽  
Ahmed Shoeir ◽  
Leonardo Borghi ◽  
...  

2006 ◽  
Vol 91 (9) ◽  
pp. 3633-3638 ◽  
Author(s):  
M. Hickey ◽  
G. Krikun ◽  
P. Kodaman ◽  
Frederick Schatz ◽  
C. Carati ◽  
...  

Abstract Context: Because of their safety and efficacy, long-term progestin-only contraceptives (LTPOCs) are well-suited for women with restricted access to health care. However, abnormal uterine bleeding (AUB) causes half of all users to discontinue therapy within 12 months. Endometria of LTPOC-treated patients display aberrant angiogenesis with abnormally enlarged, thin-walled, fragile blood vessels, inflammation, and focal hemorrhage. In this study, similar effects were observed with a new third-generation implantable LTPOC. Objective: We hypothesized that LTPOC reduces uterine and endometrial blood flow, leading to hypoxia/reperfusion, which triggers the generation of reactive oxygen species. The latter induce aberrant angiogenesis, causing AUB. Design: Endometrial perfusion was measured by laser-Doppler fluxmetry in women requesting LTPOCs. Endometrial biopsies were obtained for in vivo and in vitro experiments. Setting: The study was conducted in the Yale University School of Medicine and Family-Planning Center in Western Australia. Patients: Seven women 18 yr or older requesting implantable LTPOCs were recruited in Western Australia. Intervention: Women received etonorgestrel implants. Main Outcome: LTPOC treatment resulted in reduced endometrial perfusion and increased endometrial oxidative damage. Conclusions: We propose that LTPOCs result in hypoxia reperfusion, which leads to aberrant angiogenesis resulting in AUB.


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