Using catch-per-unit-effort data to solve spatial problems in Orange Roughy abundance estimates

<p>This thesis describes a thorough analysis of the Andes Complex orange roughy fishery, which started in 1991 and continues to date. The Andes Complex orange roughy fishery displays a rapid initial decline in catch rate, followed by a prolonged period of relatively stable catch rate. This trend is the classic feature of a hyperdepletion catch rate. The trends in the observed Andes Complex orange roughy catch rates were explored through the development of eight modified Schaefer Surplus Production Models (SPM). Each model applied a hypothesis about a mechanism catalysing the observed trend of the fishery. The SPM was modified by either adding new information to the model, or an additional parameter. The fits of the modified models were optimised to elucidate values of unknown parameters in the SPM, and these were used to create estimated abundance indicies for each model. Then I compared each index to the observed abundance index (catch rate), derived following an Exploratory Analysis. The best candidate models, which had the smallest likelihoods, BIC values, and best visual fits, were those assuming population growth rate changed midway through the fishery, or that the population size decreased following habitat damage (from trawling).</p>

Using catch-per-unit-effort data to solve spatial problems in Orange Roughy abundance estimates

<p>This thesis describes a thorough analysis of the Andes Complex orange roughy fishery, which started in 1991 and continues to date. The Andes Complex orange roughy fishery displays a rapid initial decline in catch rate, followed by a prolonged period of relatively stable catch rate. This trend is the classic feature of a hyperdepletion catch rate. The trends in the observed Andes Complex orange roughy catch rates were explored through the development of eight modified Schaefer Surplus Production Models (SPM). Each model applied a hypothesis about a mechanism catalysing the observed trend of the fishery. The SPM was modified by either adding new information to the model, or an additional parameter. The fits of the modified models were optimised to elucidate values of unknown parameters in the SPM, and these were used to create estimated abundance indicies for each model. Then I compared each index to the observed abundance index (catch rate), derived following an Exploratory Analysis. The best candidate models, which had the smallest likelihoods, BIC values, and best visual fits, were those assuming population growth rate changed midway through the fishery, or that the population size decreased following habitat damage (from trawling).</p>

Harvesting at the Ecosystem Level

Energy entering at the base of the food web places inherent constraints on total harvest from an ecosystem. Empirical relationships have been established between fishery yield and factors such as chlorophyll concentration, primary production, and other lower trophic level variables to guide management actions. Extension of network models to include harvesting has a long lineage and these models are now being employed worldwide to help guide management decisions. These static mass-balance models have been augmented with a fully dynamic modeling component to explore management options. Biomass spectrum models for exploited ecosystems have also been developed. In addition to direct effects on target species, fisheries can affect the structure and function of ecosystems through habitat damage and incidental catch of non-target organisms, including threatened and endangered species. Increasingly, the effects of climate change are being addressed in ecosystem models through their potential effect on production at all levels of the ecosystem.

Sumberdaya Kuda Laut (Hippocampus spp.) di Perairan Pulau Bintan, Teluk Lampung dan Pulau Tanakeke

<strong>Seahorse Resources (Hippocampus spp.) in the Waters of Bintan Island, Lampung Bay and Tanakeke Island</strong>.Information on seahorse resources is very limited, from 35 species of marine species listed on the IUCN redlist, 20 species are listed as "data deficient" which illustrates the lack of information related to sea horses, even for highly exploited species. This research was conducted to inventory sea horse resources (<em>Hippocampus</em> spp.), covering spesies information, size, sex ratio and density of seahorses from three potential locations, they are Bintan Island, Lampung and Tanakeke Island Waters. Field observation for seahorse resources was conducted at Bintan Island (Riau Islands Province) in March 2016, Lampung Bay (Lampung Province) in May 2016 and Tanakeke Islands (Takalar Regency, South Sulawesi) in June 2016 by purposive sampling method, interview with fisherman and collector and also literature study. A total of 5 seahorse species were found in three research locations, 4 species found in Bintan waters <em>(H. comes</em>, <em>H. spinossisimus</em>, <em>H. hystrix</em> and <em>H. kuda</em>), 2 species found in Lampung Bay (<em>H. comes</em> and <em>H. kuda</em>) and only 1 species found in Tanakeke (<em>H.barbouri</em>). Most of seahorse found during the study were categorized as sexually mature, dominated with seahorse 11-12 cm in size. The different types and densities of seahorses in the three study sites are supported by differences in habitat where seahorses are occupied. The density of seahorses tended to be low due to over-exploitation, environmental change and habitat damage. Management measures based on biological aspects and ecological conditions of each region need to be carried out for sustainable seahorse fisheries.

Population dynamics and life history of the rare arctic-alpine plant Sagina nivalis (Caryophyllaceae) on the Ben Lawers range, Scotland, UK

The flora of Scotland’s mountains is of international significance as it contains arctic-alpine species at the edge of their global range. Such rear edge populations deserve high priority investigation due to their unique local adaptations, important conservation value and because montane plants may be particularly sensitive to environmental change. Sagina nivalis is one of the rarest and least known arctic-alpines in Britain and the vast majority of plants occur within the Ben Lawers SSSI. Ten permanent plots were surveyed here from 1982-1994 by counting the number of plants and tagging and measuring individuals throughout the duration of their lives. The total number of plants present at each colony across the whole site was also recorded in 1996 and 2014. Extreme fluctuations in numbers occurred within periods of very few years and were associated with the fragile and dynamic nature of the montane habitat. Seedling mortality was very high, but age had no effect on survival rates once plants were one year old. Most were small, only lived two years and produced none or few flowers, although those that survived long enough generally reached their maximum size and flowering potential when they were five years old. The number of plants present across the whole of Ben Lawers halved between 1996 and 2014, with half of all colonies extinct and a further third in significant decline. The greatest threats to S. nivalis in Scotland were identified as habitat damage due to natural processes, sheep activity and climate change. A reduction in snow cover may cause an interaction between these factors and compromise the long-term survival of rear edge populations of this species, other rare arctic-alpines in Scotland and their associated contribution to biodiversity.

Multiplikasi Anggrek Hitam ( Coelogyne pandurata Lindl ) Pada Media Murashige Skoog (Ms) Dengan Penambahan Ekstrak Pisang Ambon dan Benzyl Amino Purin (BAP)

Black orchids (Coelogyne pandurata Lindl.) are epiphytic and endemic in Borneo. Habitat damage and over exploitation by the society can cause black orchids to be threatened with extinction. For this reason, alternative ways to increase black orchids are needed through tissue culture techniques with the addition of ambon banana extract and Benzyl Amino Purine BAP. The aim of this study was to determine the effect of ambon banana extract and BAP on the multiplication of black orchids. This research was conducted for 3 months from January to March 2018 at Pontianak Aloe Vera Center (AVC) Tissue Culture Laboratory. This study uses a Completely Randomized Design (CRD) with two factors. The first factor was ambon banana extract (0%; 2,5%; 5%; 7,5% and 10%) and the second factors BAP (0 M; 10-7M; 10-6M; 5x10-6M) with 3 replications, each of which obtained 60 trial unit. The results showed that the ambon banana extract had a significant effect on the time of budding, number of buds and number of leaves. The concentration of ambon banana extract 2,5% resulted in the fastest budding time appearing on the 11,33th day, the number of buds was 8,33 tillers, and the number of leaves was 17,67 strands.

Faktor Pendung dan Peran Brigade Pengendalian Kebakaran Hutan pada Balai Taman Nasional bukit Way Kambas

During the last 20 years, Way Kambas National Park’s area has experienced of the habitat damage, is among other things caused by a forest fire and to be triggered do not only natural faktor but also effect of is act human being. Role and also worker very needed to take care of and look after Way Kambas National Forest. Objective of this research is to learn the relation between supplementary faktors and roles of brigade of forest fire to forest fire prevention at Way Kambas National Park. Population as well as samples were 41 peoples. Data was analyzed by rank Spearman correlation. Result of research showed that the role and also in contribution of activity of forest fire control was at moderate category and no significance result on correlation between supplementary faktors and roles of brigade of forest fire.Key Word: role, forest fire, national park, brigade.

Feral swine Sus scrofa: a new threat to the remaining breeding wetlands of the Vulnerable reticulated flatwoods salamander Ambystoma bishopi

Feral swine Sus scrofa have been implicated as a major threat to sensitive habitats and ecosystems as well as threatened wildlife. Nevertheless, direct and indirect impacts on threatened species (especially small, fossorial species) are not well documented. The decline of the U.S. federally endangered reticulated flatwoods salamander Ambystoma bishopi, categorized as Vulnerable on the IUCN Red List, has been rapid and there are few remaining breeding locations for this species. The flatwoods salamander depends on complex herbaceous vegetation in all life stages, including eggs, larvae and adults. Historically sets of hog tracks have been observed only occasionally in the vicinity of monitored reticulated flatwoods salamander breeding wetlands, and damage to the wetlands had never been recorded. However, during the autumn–winter breeding season of 2013–2014 we observed a large increase in hog sign, including extensive rooting damage, in known flatwoods salamander breeding wetlands. Our objective was to assess the amount of hog sign and damage in these wetlands and to take corrective management actions to curb additional impacts. Of 28 wetlands surveyed for hog sign, presence was recorded at 68%, and damage at 54%. Of the 11 sites known to be occupied by flatwoods salamanders in 2013–2014, 64% had presence, and 55% had damage. We found that regular monitoring of disturbance in wetland habitats was a valuable tool to determine when intervention was needed and to assess the effectiveness of intervention. Habitat damage caused by feral hogs poses a potentially serious threat to the salamanders, which needs to be mitigated using methods to control and exclude hogs from this sensitive habitat.