Age and growth of the whiskery shark, Furgaleus macki, from southwestern Australia were examined using vertebral ageing and tag-recapture data. The readability of bands on the vertebral centra varied ...markedly between individuals. Four readers were used to make band counts, with the most experienced reader having the lowest 'index of average percent error' and the highest level of agreement with final counts. Marginal increment analysis indicated that opaque bands form in January. With parturition occurring from August to October, size data suggests that the first band is probably formed 15-17 months after birth. The age at maturity was estimated to be 4.5 years for males, and 6.5 years for females. The oldest male was 10.5 years, and oldest female was 11.5 years. Von Bertalanffy growth parameters for males were L^sub ∞^=121.5cm fork length, K=0.423 year^sup -1^, t^sub 0^=-0.472 years, were L^sub ∞^=120.7cm fork length, K=0.369 year^sup -1^, t^sub 0^=-0.544 years for females, and were L^sub ∞^=118.1cm fork length, K=0.420 year^sup -1^, t^sub 0^=-0.491 years for combined sexes. Data from a tag recapture study were analysed using a maximum likelihood method to verify the estimates of growth parameters from vertebral ageing. Von Bertalanffy growth parameters from the tag recapture study were L^sub ∞^=128.2cm fork length, K=0.288 year^sup -1^, t^sub 0^=-0.654 years. The two methods of estimating growth parameters produced similar results, with rapid growth until approximately 5 years of age, after which there was little increase in length.PUBLICATION ABSTRACT
The current status of the whiskery shark (
Furgaleus macki) stock in south-western Australia was assessed using an age and sex structured model. The best estimates of total and mature biomass in ...1997/1998 were 38.8% of virgin, and 23.0% of virgin, respectively. The 95% confidence intervals for total biomass were 22.7–47.2%, and for mature biomass were 13.4–36.4%. Thirteen scenarios were used to test the sensitivity of the model to catch and effort, biological, and gear parameters. The estimates of current biomass were most sensitive to variations in catch and effort data. A scenario testing the use of raw catch and effort data produced unrealistically low estimates of current biomass, while a scenario testing the hypothesis that there had been no efficiency increases in the fishery over time indicated that biomass was currently higher than indicated by the best estimate. The remainder of the scenarios tested produced estimates of total biomass between 32 and 40% of virgin, and mature biomass between 21 and 30% of virgin. Risk analysis was used to test three biological reference points: that the total biomass would be at least 40% of virgin by 2010/2011 (a management committee target), that the total biomass in 2010/2011 will not be below that of 1996/1997, and that the stock would collapse. The results of risk analysis indicates that to achieve at least a 50% probability for the first two biological reference points, annual catches would need to be below 190
tonnes until 2010. The probability of a population crash before 2010 is approximately 5% when future catches are 175
tonnes, and greater than 50% when catches are above 280
tonnes. Risk analysis indicates that there is a need to substantially reduce commercial catches if the target set by the management committee is to be met.
Relacja mówiona zarejestrowana w ramach Programu Historia Mówiona realizowanego w Ośrodku "Brama Grodzka - Teatr NN" (www.historiamowiona.teatrnn.pl). Wyraża ona wyłącznie subiektywne wspomnienia i ...poglądy świadka historii, które nie mogą być utożsamiane z oficjalnym stanowiskiem Ośrodka.
Calliobothrium pritchardae n. sp. is described from the whiskery shark, Furgaleus macki (Whitley, 1943), collected from Young Rocks in South Australia. This species differs from the 7 other known ...species of Calliobothrium in its possession of 2 rather than 3 posthook loculi. It is further distinguished from all other Calliobothrium species except Calliobothrium evani in its possession of asymmetrical hooks. The lack of an accessory piece between the bases of the axial hooks and medial axial hook bases that are longer than the lateral axial hook bases further distinguish the new species from C. evani in which an accessory piece is present and the relative lengths of the medial and lateral axial hook bases are reversed. Scanning electron microscopy reveals spiniform microtriches on the neck and proximal bothridial surfaces, filiform microtriches on the apical bothridial surfaces, and a combination of the 2 microthrix types on the distal bothridial surfaces. The extended bases of the axial hooks are densely covered with spiniform microtriches. In addition, the number of testes within worms decreases substantially in progressively posterior (older) segments. The generic diagnosis of Calliobothrium is emended to include this species with 2 rather than 3 posthook loculi.
Gaines interviews Debra Macki, a 30-year old makeup artist for the Miss Massachusetts USA contest, regarding her career, her clients, and the changes that she has seen in makeup use. She points that ...people used to just have fun with makeup on the weekends, but now they're taking more risks and doing it at the office too.
There are shelves of Holocaust books about victims, perpetrators, rescuers, and bystanders; but what about those who profited from the genocide? What happened to the property the Jews left behind?
Skeletal deformities in elasmobranchs from Australian waters Heupel, M.R; Simpfendorfer, C.A; Bennett, M.B. (Department of Anatomical Sciences, University of Queensland, St Lucia, Queensland 4072 (Australia))
Journal of Fish Biology (United Kingdom),
(1999), Letnik:
54, Številka:
5
Publication
