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Coffs Harbour, Australia

Malcolm H.A.,Solitary Islands Marine Park | Malcolm H.A.,University of New England of Australia | Smith S.D.A.,University of New England of Australia | Smith S.D.A.,Southern Cross University of Australia
Biodiversity and Conservation | Year: 2010

Effective representation of biodiversity in a marine park can be limited by lack of sampling at a suitable scale due to various methodological, logistical and taxonomic constraints. Surrogates that describe key components of biodiversity can benefit management planning and assist evaluation of zoning arrangements by improving efficiency and effectiveness of sampling. Reef fish are considered an important component of biodiversity in the Solitary Islands Marine Park (SIMP), New South Wales, Australia. Fish assemblages were surveyed using 30-min timed counts at 68 sites spread across the extent of shallow reef in the SIMP. The overall assemblage was compared with various subsets of taxa using the RELATE procedure in PRIMER to determine useful surrogates. Two families, Labridae and Pomacentridae, showed a high concordance with overall patterns and the highest correlation in estimating species richness by site. These families were the two most speciose (43, 32 species, respectively) comprising 30% of the species richness out of 66 families and 254 species. Surveying a subset of species that includes these two families has utility for marine park management in the SIMP, including evaluating the influence of 'no take' zones on assemblage patterns and systematic planning for biodiversity representation. © 2010 Springer Science+Business Media B.V.

Malcolm H.A.,Solitary Islands Marine Park | Malcolm H.A.,University of New England of Australia | Jordan A.,Climate Change and Water | Smith S.D.A.,University of New England of Australia | Smith S.D.A.,Southern Cross University of Australia
Marine Biodiversity | Year: 2010

Transition zones have complex patterns of biogeography and biodiversity which require consideration in conservation planning. Cross-shelf patterns of reef fish assemblage structure and biogeographic representation were determined for the Solitary Islands Marine Park (SIMP), positioned in a tropical-temperate overlap on the east coast of Australia. Sixty-eight sites were surveyed on shallow (<25 m) reefs across an inshore-offshore gradient, using timed counts. Tropical taxa were most prevalent, comprising 50% of the 254 species recorded. Australian endemics accounted for 23% of species, with east coast endemics (14%) predominating. There was a strong cross-shelf gradient, with species richness increasing offshore. There was also a distinct biogeographical gradient with the proportion of temperate species decreasing and tropical species increasing with increasing distance from shore. This gradient was similar for endemic and cosmopolitan species as many of the endemics were temperate or subtropical, and many of the tropical species were widespread Indo-Pacific taxa. These patterns are consistent with sites further offshore being more frequently exposed to the tropical East Australian Current (EAC). Patterns on reefs further inshore are consistent with the high levels of endemism previously reported for temperate and subtropical Australian waters. The complex cross-shelf arrangement of tropical, subtropical and temperate species results in high regional biodiversity and needs to be recognised in marine-park planning. © 2010 Senckenberg, Gesellschaft für Naturforschung and Springer.

Scott A.,National Marine Science Center | Scott A.,Southern Cross University of Australia | Malcolm H.A.,Solitary Islands Marine Park | Damiano C.,National Marine Science Center | And 2 more authors.
Marine and Freshwater Research | Year: 2011

Understanding the population dynamics of host sea anemones and their symbiotic anemonefish is important given that pressures such as aquarium collecting and bleaching events are adversely impacting their abundance in some IndoPacific locations. We examined long-term trends in anemone and anemonefish abundance at four sites within a 'no-take' zone at North Solitary Island, Australia, by comparing data from 2008 to surveys done in 1994 and 1995. Species richness was stable, comprising two anemones, Entacmaea quadricolor and Heteractis crispa, and three anemonefishes, Amphiprion akindynos, A. latezonatus, and A. melanopus. In 2008, densities of the most abundant species, E. quadricolor and A. akindynos, were substantially higher than previously recorded, with increases of up to 532% and 133%, respectively. There was a strong relationship between A. akindynos densities and anemone cover, whereas A. latezonatus had higher densities in deeper waters. Densities of this species remained similar over time, although there was a decline at one site. Heteractis crispa and A. melanopus were found in comparatively low numbers. Potential reasons for the overall increase in abundance include: protection from severe swell events, the lack of major bleaching events, the ability of E. quadricolor to reproduce rapidly by asexual reproduction, and the increasing duration of marine park protection. © CSIRO 2011.

Malcolm H.A.,Solitary Islands Marine Park | Malcolm H.A.,University of New England of Australia | Davies P.L.,Sydney Water | Jordan A.,Climate Change and Water | Smith S.D.A.,University of New England of Australia
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2011

Improved understanding of the East Australian Current (EAC) and sea-temperature patterns within the Solitary Islands region of northern New South Wales, an area where tropical and temperate faunas overlap, is an essential step in explaining cross-shelf gradients in biotic patterns. Sea temperature at ~10. m was logged using thermistors at seven stations every 30. minutes between January 2001 and December 2008. Stations were replicated in three distance-from-shore categories (<1.5; 1.5 to 6; and >6. km from the coast), corresponding with predominant assemblage patterns of reef fish. Daily, monthly, seasonal and yearly sea-temperature patterns were compared between and within stations and distance-from-shore categories. SST images were examined to determine the role of the EAC in producing short-period (2 to 4 days) temperature anomalies. Sea temperatures ranged between 16.6-27.5. °C and were highest offshore and lowest inshore. Offshore sites experienced average temperatures ~1. °C higher than nearshore sites over the 8-year study. There was considerable variation in sea temperature between years, with 2002 and 2006 being the warmest and 2007 the coolest. These patterns correspond with strong inter-annual variability of the EAC at the scale of the Solitary Islands region. The EAC influenced shelf waters most strongly during late spring/summer when temperatures were also most variable over the smallest temporal scales (hours, days). Short-period anomalies between and within stations could largely be explained by variable encroachment of the EAC across the shelf and/or colder intrusions of water forming adjacent to the coastline. Previous assumptions that the EAC strongly influences gradients in the distribution of tropical species in this nearshore region are strongly supported. © 2010 Elsevier Ltd.

Malcolm H.A.,Solitary Islands Marine Park | Malcolm H.A.,University of New England of Australia | Jordan A.,Climate Change and Water | Smith S.D.A.,University of New England of Australia | Smith S.D.A.,Southern Cross University of Australia
Aquatic Conservation: Marine and Freshwater Ecosystems | Year: 2011

1. The Solitary Islands Marine Park (SIMP) in New South Wales (NSW), Australia, has strong cross-shelf patterns of reef fish assemblages on shallow reefs (<25m). While the SIMP also contains reef at depths of up to 75m, marine communities below 25m are poorly described. The Habitat Classification System (HCS) used for planning the arrangement of zones in this marine park included three depth categories for reef: shallow (<25m); intermediate (25-60m); and deep (>60m). However, these had not been tested to determine if they adequately reflect biotic patterns. 2. Using baited remote underwater video (BRUV), fish assemblages were surveyed at 56 sites spread across shallow, intermediate, and deep reefs within the SIMP to examine spatial variation between depth categories. Relationships between assemblage patterns, depth, and four additional factors considered likely to affect assemblage patterns (distance from shore, reef type, dominant benthos, and latitude), were subsequently explored using multivariate statistical methods. 3. Reef fish assemblages differed significantly among the depth categories. Assemblage patterns for fish were strongly correlated with depth and moderately correlated with the dominant benthic assemblage. Correlations with the other factors were generally weak. Three distinct assemblages occurred on reefs <25m, 25-50m and >50m. Shallow (<25m) reefs also displayed strong cross-shelf patterns, supporting the results from other studies. Weaker cross-shelf patterns were evident at intermediate depths (25-50m). 4. Depth-based and cross-shelf categories are clearly fundamental components for a HCS that will adequately represent reef fish assemblages for conservation planning in the SIMP. Further refining the depth criteria for the intermediate/deep boundary (to 50m) improves this representation. Further research is required to determine the wider application of the refined HCS to other marine parks in NSW and to determine how well it represents other components of biodiversity. © 2011 John Wiley & Sons, Ltd..

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