Framework for Integration of Data from Remotely Operated Cameras into Recreational Fishery Assessments in Western Australia

Remotely operated cameras can be used for cost-efficient monitoring of recreational fishing activities. This report provides an overview of the current usage of cameras in recreational fishery assessments by the Department of Primary Industries and Regional Development. Since 2006, 32 remotely operated cameras have been installed at 26 locations throughout Western Australia and currently 28 cameras are in use

Reproductive cycle of Urolophus cruciatus in south-eastern Australia: does the species exhibit obligate or facultative diapause?

Observations of synchronous rapid growth of embryos and ovarian follicles in pregnant females during the half-year December–May leading to parturition, ovulation, mating, and fertilization suggest Urolophus cruciatus has the capacity for an annual reproductive cycle. Conversely, the higher proportion of the pregnant females in the population carrying eggs than carrying embryos in utero during December–May and all pregnant females in the population only carrying eggs in utero during June–November indicate a longer reproductive cycle. Analysis based on the usual assumptions implies that the species most likely exhibits a biennial cycle with ~18-month period of diapause following ovulation prior to ~6-month period of rapid embryogenesis. However, it is feasible that the period of the cycle is triennial with ~30-month period of diapause or alternatively diapause varies among individuals and varies from year to year. Rather than exhibiting a fixed-term reproductive cycle where obligatory diapause leads to parturition timed every year to provide favourable conditions for neonates, as suggested for several other chondrichthyan species, U. cruciatus may exhibit facultative diapause where the period of diapause and hence the reproductive cycle varies depending on the prevailing environmental conditions or density-dependent factors as described for many terrestrial species. U. cruciatus is highly matrotrophic (>4000 % wet mass gain from ovum to full-term embryo), litter size (1–4) increases with maternal length, sex ratio among embryos is 1:1, and male breeding condition varies seasonally with peak sperm production coinciding with female ovulation

Reproductive biology of the eastern shovelnose stingaree Trygonoptera imitata from south-eastern Australia

Abstract. In applying a quantitative approach to the reproduction of Trygonoptera imitata, the present study contributes to understanding the wide diversity in the reproductive biology of the family Urolophidae and provides insights to help determine phylogenetic relationships. This localised species is taken as bycatch in several inshore fisheries and potentially impacted by a range of other anthropogenic pressures, including introduced species, particularly in shallow-water pupping areas.T. imitata can be characterised as a species of comparatively lowmatrotrophic histotrophy with an extended period of relatively large eggs in utero (5–8 months) followed by rapid growth of the embryos (4–6 months). The reproductive cycle is annual with parturition occurring during late-February–April, followed immediately by ovulation. Mean size-at-birth is ~225mm total length and there is a ~1000% gain in mean wet mass from egg (15 g) to full-term embryo in utero (150 g), the lowest reported for any viviparous batoid. Litter size increases with maternal length, reaching a maximum of seven, and sex ratio of embryos is 1 : 1. Maximum length and estimates of the maturity–ogive parameters l50 and l95 are similar for females and males

Recreational fishing for Western Rock Lobster: estimates of participation, effort and catch from 1986/87 – 2017/18. Fisheries Research Report 299

The Western Rock Lobster (WRL) fishery is one of Australia’s largest single-species recreational and commercial fisheries. The recreational sector has a long history of harvesting this resource, and there is an ongoing need to provide annual estimates of the recreational catch due to the formal resource sharing policy adopted in 2004. Mailrecall surveys, supplemented with occasional phone-recall surveys, provide costeffective monitoring, since WRL is a single-species, licensed recreational fishery operating across large spatial and temporal scales. This report presents estimates of participation, fishing effort and retained catch from annual mail-recall surveys of randomly selected licensed Rock Lobster (RL) recreational fishers from 1986/87 to 2017/18 and provides comparisons of estimates with phone recall surveys conducted in 2001/02 and from 2015/16 to 2017/18. Participation rates were relatively stable from 1986/87–2004/05 with around 75% of licence holders fishing. Participation rates then began to decline to a low of 52% in 2011/12, before increasing to 64% by 2017/18. The total fishing effort (potting and diving combined; all RL species) increased from 0.41 million fisher days (in 1986/87) to 0.94 million (in 2017/18); an increase of 127%, over the 32 years. Total effort was low and relatively steady, 0.34–0.43 million fisher days per year during 1986/87–1990/91, then increased to 0.59 million days in 1992/93, followed by several years of higher effort occurring in 1998/99 (0.85 million days) and 2002/03 (0.92 million days). Total effort then declined to 0.41 million days in 2011/12 but has since increased to peak at 0.94 million days in 2017/18. Effort by potting was 75–90% of the total effort, compared to 10–25% by diving across all years. The estimated retained catch increased from 96 tonnes (CI 79–112) in 1986/87 to 480 tonnes (390–570) in 2017/18; an increase of 402% over the 32-years. Retained catch followed a similar trend to effort with significant peaks in 1999/00–2004/05 and in 2014/15–2017/18 but varied more from season to season, depending on factors such as lobster recruitment and management changes. Potting harvested 70–85% of the lobsters, compared to 15–30% by diving across all years. The trends in participation, fishing effort and retained catch vary over the 32-time period and have been influenced by various societal, biological, and management factors, including changing abundance and recruitment of RL stocks and management regulations (i.e. season length, size and bag limits). Phone-recall surveys were introduced as an alternative method of estimating recreational catch, due to declining survey responses for the mail-recall surveys. Phone-recall surveys were less biased from survey non-response and produced lower estimates of participation, fishing effort and retained catch than the mail survey. The lower estimates in the phone-recall survey were predominantly from pot fisher responses, whereas estimates for dive fishing were generally similar between survey methods

Recreational fishing for Western Rock Lobster: estimates of participation, effort and catch from 1986/87 – 2017/18. Fisheries Research Report 299

The Western Rock Lobster (WRL) fishery is one of Australia’s largest single-species recreational and commercial fisheries. The recreational sector has a long history of harvesting this resource, and there is an ongoing need to provide annual estimates of the recreational catch due to the formal resource sharing policy adopted in 2004. Mailrecall surveys, supplemented with occasional phone-recall surveys, provide costeffective monitoring, since WRL is a single-species, licensed recreational fishery operating across large spatial and temporal scales. This report presents estimates of participation, fishing effort and retained catch from annual mail-recall surveys of randomly selected licensed Rock Lobster (RL) recreational fishers from 1986/87 to 2017/18 and provides comparisons of estimates with phone recall surveys conducted in 2001/02 and from 2015/16 to 2017/18. Participation rates were relatively stable from 1986/87–2004/05 with around 75% of licence holders fishing. Participation rates then began to decline to a low of 52% in 2011/12, before increasing to 64% by 2017/18. The total fishing effort (potting and diving combined; all RL species) increased from 0.41 million fisher days (in 1986/87) to 0.94 million (in 2017/18); an increase of 127%, over the 32 years. Total effort was low and relatively steady, 0.34–0.43 million fisher days per year during 1986/87–1990/91, then increased to 0.59 million days in 1992/93, followed by several years of higher effort occurring in 1998/99 (0.85 million days) and 2002/03 (0.92 million days). Total effort then declined to 0.41 million days in 2011/12 but has since increased to peak at 0.94 million days in 2017/18. Effort by potting was 75–90% of the total effort, compared to 10–25% by diving across all years. The estimated retained catch increased from 96 tonnes (CI 79–112) in 1986/87 to 480 tonnes (390–570) in 2017/18; an increase of 402% over the 32-years. Retained catch followed a similar trend to effort with significant peaks in 1999/00–2004/05 and in 2014/15–2017/18 but varied more from season to season, depending on factors such as lobster recruitment and management changes. Potting harvested 70–85% of the lobsters, compared to 15–30% by diving across all years. The trends in participation, fishing effort and retained catch vary over the 32-time period and have been influenced by various societal, biological, and management factors, including changing abundance and recruitment of RL stocks and management regulations (i.e. season length, size and bag limits). Phone-recall surveys were introduced as an alternative method of estimating recreational catch, due to declining survey responses for the mail-recall surveys. Phone-recall surveys were less biased from survey non-response and produced lower estimates of participation, fishing effort and retained catch than the mail survey. The lower estimates in the phone-recall survey were predominantly from pot fisher responses, whereas estimates for dive fishing were generally similar between survey methods

Ecological vulnerability of the chondrichthyan fauna of southern Australia to the stressors of climate change, fishing and other anthropogenic hazards

We develop a potentially widely applicable framework for analysing the vulnerability, resilience risk and exposure of chondrichthyan species to all types of anthropogenic stressors in the marine environment. The approach combines the three components of widely applied vulnerability analysis (exposure, sensitivity and adaptability) (ESA) with three components (exposure, susceptibility and productivity) (ESP) of our adaptation of productivity–susceptibility analysis (PSA). We apply our 12-step ESA‒ESP analysis to evaluate the vulnerability (risk of a marked reduction of the population) of each of 132 chondrichthyan species in the Exclusive Economic Zone of southern Australia. The vul nerability relates to a species’ resilience to a spatial (or suitability) reduction of its habitats from exposure to up to eight climate change stressors. Vulnerability also relates to anthro pogenic mortality added to natural mortality from exposure to the stressors of five types of fishing and seven other types of anthropogenic hazards. We use biological attributes as risk factors to evaluate risk related to resilience at the species or higher taxonomic level. We evaluate each species’ exposure to anthropogenic stressors by assigning it to one of six ecological groups based on its lifestyle (demersal versus pelagic) and habitat, defined by bathymetric range and substrates. We evaluate vulnerability for 11 scenarios: 2000– 2006 when fishing effort peaked; 2018 following a decade of fisheries management reforms; low, medium and high standard future carbon dioxide equivalent emissions sce narios; and their six possible climate–fishing combinations. Our results demonstrate the value of refugia from fishing and how climate change exacerbates the risks from fishing.Fil: Walker, Terence I.. Monash University; Australia. The University of Melbourne; AustraliaFil: Day, Robert W.. The University of Melbourne; AustraliaFil: Awruch, Cynthia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Tasmania; AustraliaFil: Bell, Justin D.. Institute For Marine And Antarctic Studies; AustraliaFil: Braccini, Juan Matias. Wa Fisheries And Marine Research Laboratories; AustraliaFil: Dapp, Derek R.. Monash University; AustraliaFil: Finotto, Licia. Monash University; AustraliaFil: Frick, Lorenz H.. Monash University; AustraliaFil: Garcés-García, Karla C.. Universidad Veracruzana; México. The University of Melbourne; AustraliaFil: Guida, Leonardo. Monash University; AustraliaFil: Huveneers, Charlie. Flinders University; AustraliaFil: Martins, Camila L.. Monash University; AustraliaFil: Rochowski, Bastien E.A.. The University of Melbourne; AustraliaFil: Tovar-Ávila, Javier. Inapesca; MéxicoFil: Trinnie, Fabian I.. Wa Fisheries And Marine Research Laboratories; AustraliaFil: Reina, Richard D.. Monash University; Australi