Will we see you again? Population evaluation of Palinurus elephas inside a marine reserve from Capture-Mark-Recapture data

To achieve an effective management of the marine exploited populations it is necessary to understand their dynamics and the processes driving short- and long-term changes. Key population parameters such as survival and movement can be estimated by means of capture-mark-recapture studies, based on the capture, tagging and re-encounter of the individuals at later times. The Cormack-Jolly-Seber model, which assesses the apparent survival i and the recapture rate pi of a population conditional on first capture, was applied to European spiny lobster Palinurus elephas data from the Columbretes islands marine reserve to evaluate the evolution of this population after closure to fishing over. Particularly strong winter conditions were reported for some years during the period of study whcih were reflected as an increase in the estimate of the encounter probability and a decrease in their survival rate. P. elephas showed a relatively high plasticity against short-term environmental effects, with the apparent survival quickly returning to pre-storm levels. Also a slight increase in survival was identified for this protected population over time. These preliminary results are discussed in terms of the factors affecting the dynamics of this population and the implications for the management of this exploited stoc

Reproductive seasonality and embryo development in the draughtboard shark Cephaloscyllium laticeps

The draughtboard shark Cephaloscyllium laticeps is a common oviparous catshark found in Australia. Studies on the reproductive seasonality of catsharks and the reproductive endocrinology of oviparous elasmobranchs are limited to a few species. The aim of the present study was to investigate the reproductive seasonality and embryo development of C. laticeps using morphological and endocrine parameters. Macroscopic examinations of the reproductive system and embryo stages were recorded. The steroid hormones 17β- oestradiol (E2) and progesterone (P4) were measured in females, and testosterone (T) in both sexes. Females laid eggs throughout the year, but with a peak in egg deposition between January and June. Female T levels were higher in the middle of the year. Elevated P4 values coincided with the period of egg deposition, whereas E2 was depressed in the middle of the egg deposition stage. Females laid eggs in the absence of males for 15 months, and eggs were laid in pairs at monthly intervals. Hatching occurred after 12 months. Variability in gonadosomatic index, percentage of sperm in seminal vesicles, and plasma T levels for males indicated that males were reproductively active throughout the year

Will we see you again? Population evaluation of Palinurus elephas inside a marine reserve from Capture-Mark-Recapture data

To achieve an effective management of the marine exploited populations it is necessary to understand their dynamics and the processes driving short- and long-term changes. Key population parameters such as survival and movement can be estimated by means of capture-mark-recapture studies, based on the capture, tagging and re-encounter of the individuals at later times. The Cormack-Jolly-Seber model, which assesses the apparent survival i and the recapture rate pi of a population conditional on first capture, was applied to European spiny lobster Palinurus elephas data from the Columbretes islands marine reserve to evaluate the evolution of this population after closure to fishing over. Particularly strong winter conditions were reported for some years during the period of study whcih were reflected as an increase in the estimate of the encounter probability and a decrease in their survival rate. P. elephas showed a relatively high plasticity against short-term environmental effects, with the apparent survival quickly returning to pre-storm levels. Also a slight increase in survival was identified for this protected population over time. These preliminary results are discussed in terms of the factors affecting the dynamics of this population and the implications for the management of this exploited stoc

Fishing for the impacts of climate change in the marine sector: A case study

Purpose – This paper aims, using a case study-based research approach, to investigate the role of climate and non-climate drivers in shaping three commercial marine sectors: fishing, aquaculture and marine tourism. Essential elements of climate change research include taking a whole of systems approach, which entails a socio-ecological perspective, and considering climate challenges alongside other challenges faced by resource users. Design/methodology/approach – The analysis is based on information gained using in-depth semi-structured interviews in a coastal community in southeast Australia. Even though climate drivers differ, the economic sectors of this community are representative of many similar coastal communities around Australia. Findings – Results show that at a community level, people involved in, or associated with, marine sectors are aware of climate change impacts on the marine environment. Even though many may not see it as a pressing issue, the potential effect of climate change on business profitability was recognised. Both the profitability of commercial fishing and aquaculture (oysters) was affected through mostly a downward pressure on product price, while marine tourism profitability was mainly affected through changes in the number of visitors. Research limitations/implications – A case study approach is inherently case study-specific – although generalities from complex system representation, built on local survey respondent observation and knowledge of the combined and linked physical–biological-, social-, economic- and governance drivers. This study shows the importance of a holistic approach; yet, researchers must also consider all community sectors and cross-regional investigations to avoid future resource conflicts. Practical implications – A number of positive impacts from climate-driven change, mainly from windfall economic benefits of geographically relocated species, were reported for commercial- and charter fishing. However, no positive impacts were reported for the aquaculture- and dive sector. In the aquaculture sector, climate drivers were of great significance in industry participation, while participation in commercial fishing was mainly driven by socio-economic factors. Social implications – To ensure the combined marine sectors retain a viable component of coastal communities’ economic focus, there is a need to understand what drives participation in the marine sector, and what the role of climate change is in this. To fully understand the ramifications of climate change in the marine environment, it is essential to understand its impacts across all marine sectors. Originality/value – Combining the different domains with climate drivers allows for identification and assessment of targeted adaptation needs and opportunities and sets up a comprehensive approach to determine future adaptation pathways

Redmap Australia: challenges and successes with a large-scale citizen science-based approach to ecological monitoring and community engagement on climate change

Citizen science includes a suite of research approaches that involves participation by citizens, who are not usually trained scientists, in scientific projects. Citizen science projects have the capacity to record observations of species with high precision and accuracy, offering the potential for collection of biological data to support a diversity of research investigations. Moreover, via the involvement of project participants, these projects have the potential to engage the public on scientific issues and to possibly contribute to changes in community knowledge, attitudes and behaviors. However, there are considerable challenges in ensuring that large-scale collection and verification of species data by the untrained public is a robust and useful long-term endeavor, and that project participants are indeed engaged and acquiring knowledge. Here, we describe approaches taken to overcome challenges in creation and maintenance of a website-based national citizen science initiative where fishers, divers, and other coastal users submit opportunistic photographic observations of ‘out-of-range’ species. The Range Extension Database and Mapping Project (Redmap Australia) has two objectives, (1) ecological monitoring for the early detection of species that may be extending their geographic distribution due to environmental change, and (2) engaging the public on the ecological impacts of climate change, using the public’s own data. Semi-automated ‘managed crowd-sourcing’ of an Australia-wide network of scientists with taxonomic expertise is used to verify every photographic observation. This unique system is supported by efficient workflows that ensures the rigor of data submitted. Moreover, ease of involvement for participants and prompt personal feedback has contributed to generating and maintaining ongoing interest. The design of Redmap Australia allows co-creation of knowledge with the community – without participants requiring formal training – providing an opportunity to engage sectors of the community that may not necessarily be willing to undergo training or otherwise be formally involved or engaged in citizen science. Given that capturing changes in our natural environment requires many observations spread over time and space, identifying factors and processes that support large-scale citizen science monitoring projects is increasingly critical.Gretta T. Pecl, Jemina Stuart-Smith, Peter Walsh, Dianne J. Bray, Martha Kusetic, Michael Burgess, Stewart D. Frusher, Daniel C. Gledhill, Oliver George, Gary Jackson, John Keane, Victoria Y. Martin, Melissa Nursey-Bray, Andrew Pender, Lucy M. Robinson, Keith Rowling, Marcus Sheaves, and Natalie Moltschaniwsky

Distribuição espacial, sazonal e estrutura populacional do caranguejo Aratus pisonii (H. Milne Edwards) (Crustacea, Decapoda, Sesarmidae) do manguezal de Itacuruçá, Rio de Janeiro, Brasil Spatial and seasonal distribution and population structure of the crab Aratus pisonii (H. Milne Edwards) (Crustacea, Decapoda, Sesarmidae) in Itacuruçá mangrove, Rio de Janeiro, Brazil

Este trabalho teve por objetivo analisar a distribuição espacial e sazonal e a estrutura populacional do caranguejo arborícula Aratuspisonii (H. Milne Edwards, 1837). O trabalho foi realizado através de coletas mensais de junho de 2000 a maio de 2001, para estudo da estrutura populacional e coletas sazonais de janeiro a outubro de 2002 para o estudo da distribuição espacial e sazonal, dividiu-se o manguezal em três áreas. Para a distribuição espacial e sazonal foram capturados 694 indivíduos sendo 45% na área 1, 36% na área 2 e 19% na área 3. O número de indivíduos apresentou diferença significativa na distribuição espacial entre as áreas 2 e 3. Para o estudo da estrutura populacional foi capturado um total de 742 caranguejos, sendo 59% machos, 32,7% fêmeas e 8,3% fêmeas ovígeras. A razãosexual obtida foi de 1: 0,69 (macho:fêmea) e a largura da carapaça variou de 9,6 a 25,0 mm em machos e de 5,5 a 24,9 mm em fêmeas. A distribuição da freqüência em classes de tamanho foi unimodal e os machos foram mais freqüentes entre as classes de 19,1 a 21,0 mm LC, enquanto as fêmeas entre 17,1 a 19,0 mm LC. A razão sexual ao longo de cada classe de tamanho demonstrou predominância de machos em quase todas as classes, exceto entre as classes de 5,1 a 7,0 e 7,1 a 9,0 mm de LC.<br>This work was performed by monthly sampling from June 2000 to May 2001 for population structure studies and by seasonal sampling from January to October 2002 for space and seasonal distribution studies, dividing the mangrove in three different areas. On the space-seasonal distribution study, 694 crabs were caught, where 45% was captured in area 1,36% in area 2 and 19% in area 3. There were significant differences between the number of individuals between area 2 and 3. For the population structure study a total of 742 crabs were captured, being 59% male, 32.7% female and 8.3% ovigerous females. The sex ratio was 1:0.69 (male:female), and the carapace width ranged from 9.6 to 25.0 mm CW in males and from 5.5 to 24.9 mm CW in females. The size class distribution was unimodal and the males were more frequent between 19.1 to 21.0 mm CW, while females between 17.1 to 19 mm CW. The sex ratio along each size class showed the male predominance in almost all classes except between the classes of 5.1 to 7.0 and 7.1 to 9.0 mm CW