Changes in rocky reef fish assemblages throughout an estuary with a restricted inlet

Rocky reef habitat is common in many estuaries, yet its role as a habitat for fishes is poorly understood. There is also limited understanding of how access of coastal species into estuaries and habitat quality can affect the distribution of rocky reef fishes within estuaries. This study used baited remote underwater video stations to determine spatial patterns in fish assemblages associated with rocky reef habitat throughout a barrier estuary with a permanently open but restricted inlet. Estuarine rocky reefs provided habitat for a diverse assemblage of fishes, many of which were large juveniles and subadults. In the absence of a pronounced salinity or temperature gradient, a clear transition in fish assemblages occurred from coastal waters, through the inlet channel, to the central estuary, and into the inner estuary. The inlet channel, notably its narrowness and length, limits tidal input into this estuary, which acts as a significant impediment to the dispersal of many coastal fishes, and insufficient habitat excludes many coastal rocky reef species from the inner estuary. This study highlights the need to recognise estuarine rocky reefs as providing habitat for diverse fish assemblages and the role inlets play in restricting access of coastal species. © 2013 Springer Science+Business Media Dordrecht

Contrasting coral community structures between natural and artificial substrates at Koh Tao, Gulf of Thailand

Concrete cubic frames and decommissioned steel naval vessels have been deployed in Thailand liberally to act as artificial substrates for coral restoration and marine recreation. We assessed recruitment at such substrate types at Koh Tao, Gulf of Thailand, and compared the community structure of scleractinian corals between artificial substrates and nearby natural reefs. Our results from a sample of 2677 recruits from nine sites highlighted significant differences in community structure between both reef types. Investigations of variables including time since deployment, distance from the natural reef, and seafloor depth revealed only the latter as a possible influencing factor. The diversity of recruits could not be explained by dynamics in coral spawning, and were found to represent groups with lower structural complexity. Our results suggest that coral community structure on artificial and natural reefs differs and supports distinct ecological and functional roles

Aphrati and Kato Syme: Pottery, Continuity, and Cult in Late Archaic and Classical Crete

The analysis of ceramics from Aphrati sheds valuable new light on the history of this Cretan settlement and on its relationship with a nearby rural sanctuary at Kato Syme in the Late Archaic and Classical periods. It has long been held that Aphrati was deserted from ca. 600 to 400 B.C. A pottery deposit from the domestic quarter, however, now supports occupation of the city during this period. A ceramic classification system is presented and the morphological development and absolute chronology of several key shapes at Aphrati and Kato Syme are plotted. Historical implications of the ceramic evidence are also explored

Oil and Gas Platforms on Ship Shoal, Northern Gulf of Mexico as Habitat for Reef-Associated Organisms

Nearshore Louisiana has experienced substantial changes within the last half-century, including the annual formation of the world’s second largest hypoxic zone and the construction of thousands of oil and gas platforms (rigs). Ship Shoal and its rigs may provide important substrate in nearshore Louisiana because rigs act as de facto artificial reefs and the shoal’s bottom waters were well oxygenated on 43% of days when surrounding areas were hypoxic. From July to September of 2014, fish assemblages and hydrography were compared at shoal rigs, rigs inshore of the shoal, and rigs offshore of the shoal, and stone crab populations were compared at rigs on and off the shoal. A camera array and YSI sonde were used to characterize fish assemblages and hydrography at shoal rigs, rigs inshore, and offshore of the shoal. Stone crab densities were estimated with visual counts, and their life history was characterized by removing a subsample of stone crabs for identification and measurements. Fish assemblage composition was significantly different between shoal rigs, rigs inshore, and rigs offshore of the shoal (P\u3c0.05). The most notable difference between assemblages was greater contribution of demersal fishes at shoal rigs than rigs inshore and offshore of the shoal. Hypoxia was intermittent at shoal rigs and persistent at rigs inshore and offshore of the shoal. Mean hypoxia thickness (meters of hypoxic water) was significantly greater (P\u3c0.05) at rigs inshore (2.6 m) and offshore of the shoal (3.1 m) than it was at shoal rigs (0.6 m). Crab densities were roughly twice as high on as they were off the shoal (mean 4.0 vs. 1.8 stone crabs/m2; P\u3c0.05), and the carapace width where 50% of females were ovigerous was 26.4 mm smaller for females off than on the shoal (P=0.057). Shoal rigs and rigs in surrounding waters provide important substrate for reef- associated organisms, although higher contribution of demersal fishes and densities of SCs at shoal rigs than rigs in surrounding waters suggest that shoal rigs are of higher relative importance. These findings suggest that further mining of Ship Shoal and removal of rigs may be detrimental to reef-associated organisms in nearshore Louisiana

Managing Diversity: Power-sharing or Control? A Comparison between India and Sri Lanka

Based on the case studies of India and Sri Lanka, the paper combines conceptual and empirical findings on power-sharing arrangements as a key to conflict management in deeply divided, post-colonial societies. The two countries were chosen because of the similarity of their ethnopolitical conflicts but also because of their differences in conflict management practices and outcomes. For the case study on India, I argue that by applying power sharing principles the conflicts resulting from demands of minorities, such as homeland and linguistic recognition, were met through provisions based on the principle of segmental autonomy; demands for proportional representation in political decision-making were met through the specificity of “centric-regional” parties and through policies of reservation; whereas demands for security, such as preservation of cultural identity were met through segmental autonomy as well as formal and informal blocking rights. Conversely, Sri Lanka was originally blessed with favorable conditions at independence, but sub-optimal political choices after independence turned “milder ethnic conflict” into a protracted civil war. I argue that a policy based on a majoritarian control system was at the root of the ethnic conflict in Sri Lanka. Two interrelated claims are advanced. Based on the consociational approach, 1) in a deeply divided society, conflict regulation can be achieved only through adoption of power sharing arrangements; and based on the majoritarian “control” approach: 2) in a deeply divided society majoritarian practices will exacerbate rather than regulate a conflict

Patterns of Reef Fish Larval Supply to Petroleum Platforms in the Northern Gulf of Mexico.

Surveys of ichthyoplankton assemblages were conducted from four oil and gas platforms located in the northern Gulf of Mexico from November 1994 through July 1997. Diurnal collections, supplemented with light trap collections from the surface and -20 m depth, were taken quarterly during 1994 and 1995. Quarterly ichthyoplankton sampling at dawn and dusk only during 1996 and 1997 were supplemented with surface lighted plankton net collections. Of the 36,676 individuals collected, epipelagic (neretic and oceanic Clupeiformes, neretic Carangidae and Lutjanidae, as well as oceanic Scombridae) and mesopelagic (Myctophidae and Gonostomatidae) families comprised the majority of the ichthyoplankton. Reef-dependent (e.g., Pomacentridae, Labridae, and Acanthuridae) families that dominated the adult fish communities at the platforms were either absent or very rare from both ichthyoplankton and light trap collections. Large-scale water mass movements, which primarily determine the transport of planktonic organisms as well as the linkage between potential source (natural reefs, hard bottom banks, and other platform structures) and sinks (platform artificial reef sites) were investigated with blended TOPEX/POSEIDON and ERS-2 radar altimetry. Serranid larvae collected from the plankton were aged by use of sagittal otoliths in order to estimate their transit time from natal source areas. Transit time in the plankton averaged 14.5 days. Seasonal transport envelopes showed that recruitment to mid-shelf and shelf-break platforms were influenced primarily by mesoscale warm-core and cold-core eddies. Within these seasonal envelopes, the numbers of artificial reef platforms potentially serving as source locations for recruitment greatly outnumbered the natural reef sites. Scuba diver and remotely operated vehicle surveys of juvenile and adult stage reef-dependent species were also conducted on the mid-shelf and shelf-break platforms. These were compared to underwater video footage of natural reef sites (National Marine Fisheries Service, SEAMAP fish trap/video gear) in order to establish correspondence between the taxa supplied to the platforms and the surrounding hard-bottom communities. Bray-Curtis similarity cluster analysis and multidimensional scaling of adult and juvenile reef-dependent fish communities showed that platform habitats had a biological character more like natural reef sites found in the eastern Gulf of Mexico, where little recruitment was shown to originate

Macrobenthos used to validate multi-criteria derived marine biodiversity spatial zones in KwaZulu-Natal, South Africa.

Masters Degree. University of KwaZulu-Natal, Durban.Compared to terrestrial ecosystems, the characteristics of marine ecosystems remain largely under-explored. Marine and coastal ecosystems provide a number of ecological services and societal benefits (resources for commercial opportunity, food, recreation, and transport) which, in turn, has developed a strong reliance on these ecosystems. However, the increasing direct extraction of living and non-living resources and effects of urbanisation of adjacent coasts has placed a significant loss of habitats and associated essential diversity. To conserve biodiversity and retain specific goods and services provided by these ecosystems, marine conservation plans aim to protect spatial areas that are critical in the support of these benefits. Due to the paucity of adequate biological data and the prohibitive cost of directly sampling benthic biota over large areas, the most effective means of developing benthic habitat maps, used as biodiversity surrogates, is to use commonly available marine abiotic attributes. In KwaZulu-Natal (KZN), through marine spatial planning (MSP) the derivation of a marine conservation plan is well underway. The next step is to expedite the plan by investigating whether surrogates for biodiversity exist at different ecosystem levels, one being the infauna of unconsolidated sediments, mid-shelf 50-80 m. This work presents an outcome of the ACEP ‘Surrogacy Project’ that assessed whether predefined biodiversity zones (biozones) represent the taxonomic/functional attributes of macrobenthic communities. Biozones were subdivided into various subclusters from Richards Bay to uMkhomazi with 19 (57 replicates) stations sampled during the winter of 2014 across the biozones to represent replicate ‘treatments’. Macrobenthic communities were classified taxonomically, to the lowest level possible, and then on biological traits. Community patterns were investigated along the mid-shelf, and related to measurable biophysical factors. Environmental parameters measured included sedimentary characteristics as well as the bottom 5 m of water column characteristics per station. A total 33 215 individuals belonging to 634 taxa were recorded along the mid-shelf, of which the majority were Polychaeta and Crustacea, with the latter being highly abundant. Cluster analysis resolved into seven taxonomic groups distributed according to different habitats that are characteristic to the KZN shelf. The use of coarser taxonomic resolution (Phylum-Genus) or indicator taxa (Polychaeta and Amphipoda) as surrogates for total community richness were independently investigated using the same macrofaunal abundance data. Results showed similar clustering of samples to total fauna (Species-level) when data were analysed at Family-Genus taxonomic level and at Polychaeta indicator taxa, suggesting that the same amount of information was being gained using data based on these taxonomic level and indicator taxa. The results of the BIOENV analyses were also broadly similar for both taxonomic levels of analyses, in terms of both the proportion of the variation in assemblage structure explained by the selected environmental variables and the choice of selected variables. These results suggested that the information gathered at Family-Genus level and Polychaeta indicator can be used as a proxy for the whole macrobenthic community. This has important implications for future studies and for MSP. Using nine traits, across 51 categories, four main functional groups were found off Thukela, Zinkwazi to Durban, and Durban to uMkhomazi. The groups were characterised as being free-living carnivores, hard-skeleton direct-developing omnivores, and soft-bodied or hard-shelled omnivores with planktotrophic larvae. These patterns were explained by the KZN shelf habitat complexity, including level of different sediment grains, TOC, carbonates, water column turbidity, salinity, dissolved oxygen and temperature. Thus far, distribution patterns and functional attributes of the macrobenthos do not fully agree with modelled biozone separations (KZN MSP biozone model). Because they are an important component of marine ecosystem functioning, biozone model derivations require the addition of a macrobenthic component, in particular information about diversity patterns, to identify areas for conservation. Suggested, is a refinement of the current benthic habitat layer by incorporating biological data. Further, by using validated sediment distribution, taxonomic and functional attributes that determine soft-bottom macrofaunal distribution at a variety of spatial scales, an alternative biozone model to the current MSP predefined biozones was proposed. This multi-approach resolved into a simplified model with four biozones. These are likely better predictors of spatial variation in ecosystem processes and biodiversity as domains that are biologically informed, and are a key requirement for effective marine management. This study demonstrates the critical importance of testing assumptions about surrogacy and an approach for refining surrogates. Further studies are required to establish whether the proposed model adequately represents other ecological components (e.g. epifauna). The findings of this study contribute significantly to existing local knowledge, including augmenting and refining taxonomic information of the KZN shelf. In addition, this study subsidises poor information for large spatial areas in local and national marine conservation plans. The proposed biozone model may facilitate an understating of ecosystem process in the region and contributes to integrated marine management

Biodiversity patterns in False Bay: an assessment using underwater cameras

Understanding how marine biodiversity is distributed, and what drives these patterns, relies on good descriptions of marine ecosystems. This information should inform the protection of biodiversity and guide its management. Relationships between marine landscapes and biodiversity therefore need to be described at scales that are useful to regional management. Simultaneous sampling of marine biodiversity and the seafloor is challenging, so baseline ecosystem descriptions are often mismatched in their abiotic and biotic components. Cameras can sample the seafloor and its associated biodiversity concurrently, with good coverage and at low cost. These are important considerations for sustainable monitoring to inform conservation management in resource-limited regions. Terrestrial landscape characterisations cannot simply be translated to the ocean because interpreting remote ocean terrain assessments in a manner relevant to ecological analysis is complicated by depth, circulation, light attenuation, and other oceanographic variables. The integration of some of these concepts into rapid marine biodiversity assessments therefore needs ground-truthing where they are applied in new regions, to advance sustainability in long-term marine monitoring. This thesis investigated the relationship between landscape composition and benthic marine biodiversity in False Bay, South Africa using novel methods that extended biodiversity sampling across more depths and habitats than any single, previous survey of the bay. This study's approach piloted sampling and interpreting the marine landscape and biodiversity over matching spatial and temporal scales. The coverage, repeatability and ecosystem-level scale applied to this study make it a useful basis to develop monitoring protocols that are appropriate to conservation management at relevant regional scales. New insights for the region include a) a new description of the seafloor using classifications that explain the variation in epibenthic megafauna and ichthyofauna communities, b) a quantitative account of the epibenthic megafauna on the eastern reefs where species diversity was highest, and c) the synthesis of seafloor descriptions with the epibenthic megafauna and ichthyofauna to describe nine regions of False Bay, relative to two previous descriptions of "grounds". Photographs and multibeam bathymetry characterised the seafloor on eight transects across the bay and were ground-truthed by grab samples repeated at representative sites. Two new classifications were applied to describe the seafloor. Horizontal seafloor heterogeneity was highest in the east, and reef was distributed along the eastern and western margins. The Collaborative and Automated Tools for Analysis of Marine Imagery (CATAMI) scheme captured accurate broad-scale descriptions of the physical landscape when applied to photographs. Grabs are still needed to provide fine-scale particle size data on soft sediments where most invertebrate diversity is likely infauna. However, CATAMI abstracts fine-scale sediment variation into simpler groupings more useful for rapid ecosystem assessment. Photographic sampling is repeatable, which is useful for long-term ecosystem monitoring. Photographs taken using a jump camera rig assessed the epibenthic megafauna across habitats and along depth gradients. Rényi diversity showed that species diversity increased in shallow waters up to 40 m, reaching a peak between 30 and 40 m, before decreasing with increasing depth. Species diversity was highest in the east, where seafloor heterogeneity was also highest. This result is interesting because eastern False Bay falls mostly outside the current marine protected area (MPA) network and has been relatively under-represented in previous surveys. The jump camera documents ecosystem-level biodiversity patterns and processes, and the random point count method in Coral Point Count (CPCe) is useful to assess community composition and cover on reefs. The relative abundance and distribution of ichthyofauna were assessed using baited remote underwater video systems (BRUVs). Fifty-seven fish species from 30 families were recorded between 4 and 84 m. Rényi diversity showed that species richness was similar for reef and sand overall, but the Shannon-Wiener diversity index (H') was significantly higher on reef sites than on sand sites (t = 1.972, p < 0.0001). Species richness for the whole bay was similar in winter and summer, which indicates that the same species are likely present year-round; however, the Shannon-Wiener diversity index was significantly higher in winter (t = 1.973, p < 0.013) and evenness was greater in winter at the level of the site. These findings highlight the difficulty in protecting sufficient sand habitat to encompass the patchy distribution of sand-associated species and highlight seasonal differences in optimal visibility for future camera monitoring surveys by conservation management. There are clear patterns in the marine biodiversity of False Bay, at various scales, that can be detected using novel methods for the region. The study's approach to classifying both the landscape and its associated biodiversity creates a framework for future ecosystem threat assessment that can be applied elsewhere, especially along the South African coastline

Science-based restoration monitoring of coastal habitats, Volume Two: Tools for monitoring coastal habitats

Healthy coastal habitats are not only important ecologically; they also support healthy coastal communities and improve the quality of people’s lives. Despite their many benefits and values, coastal habitats have been systematically modified, degraded, and destroyed throughout the United States and its protectorates beginning with European colonization in the 1600’s (Dahl 1990). As a result, many coastal habitats around the United States are in desperate need of restoration. The monitoring of restoration projects, the focus of this document, is necessary to ensure that restoration efforts are successful, to further the science, and to increase the efficiency of future restoration efforts