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Yungaburra, Australia

Claydon J.A.B.,The School for Field Studies | Mccormick M.I.,James Cook University | Jones G.P.,James Cook University
Journal of Fish Biology | Year: 2014

Spawning sites used by one or more species were located by intensively searching nearshore coral reefs of Kimbe Bay (New Britain, Papua New Guinea). Once identified, the spawning sites were surveyed repeatedly within fixed 5m radius circular areas, for >2000 h of observations ranging from before dawn to after dusk spanning 190 days between July 2001 and May 2004. A total of 38 spawning sites were identified on the seven study reefs distributed at an average of one site every 60m of reef edge. Pelagic spawning was observed in 41 fish species from six families. On three intensively studied reefs, all 17 spawning sites identified were used by at least three species, with a maximum of 30 different species observed spawning at a single site. Spawning was observed during every month of the study, on all days of the lunar month, at all states of the tide and at most hours of the day studied. Nevertheless, the majority of species were observed spawning on proportionately more days from December to April, on more days around the new moon and in association with higher tides. The strongest temporal association, however, was with species-specific diel spawning times spanning<3h for most species. While dawn spawning, afternoon spawning and dusk spawning species were differentiated, the time of spawning for the striated surgeonfish Ctenochaetus striatus also differed significantly among sites. The large number of species spawning at the same restricted locations during predictable times suggests that these sites are extremely important on this low-latitude coral reef. © 2014 The Fisheries Society of the British Isles. Source

Schneller A.J.,Skidmore College | Irizarry A.,The School for Field Studies
Ocean and Coastal Management | Year: 2014

Public art in Mexico has historically served as a platform for protest and social commentary. The purpose of this action research was to document sea turtle murals throughout Baja California Sur (B.C.S.), Mexico and to better understand the potential relevance of public art as an impetus for fostering pro-environmental attitudes, and the extent to which murals are a useful tool in efforts to protect the marine environment and the recovery of endangered species. Through qualitative research, we conducted 333 surveys and interviews with both adult and student participants in nine B.C.S. communities. Through descriptive narratives of participant responses, and Type I tabulations, we found evidence of outcomes that sea turtle murals may have in relation to respondent environmental attitudes about support for marine protections and the recovery of endangered species of sea turtles. Unexpected results from semi-structured interviews with respondents pointed weakly to the potential for murals in helping to shape pro-environmental behaviors towards the treatment and recovery of endangered sea turtles. The results of this action research may provide useful insights for improving management practices during future efforts to protect and restore marine environments and endangered species. That is, public participation in strategically placed community accessible art, may prove to be a valuable and innovative component of a broader suite of outreach and education initiatives used for bolstering community responsibility and empowerment for conservation of the marine environment. © 2013 Elsevier Ltd. Source

Lopez-Calderon J.,Autonomous University of Baja California Sur | Riosmena-Rodriguez R.,Autonomous University of Baja California Sur | Rodriguez-Baron J.M.,National Polytechnic Institute of Mexico | Carrion-Cortez J.,Autonomous University of Baja California Sur | And 4 more authors.
Marine Biodiversity | Year: 2010

Human impact and global warming are driving major modifications to the world's ecosystems, the coastal zone being one of the most damaged. Seagrass meadows constitute coastal communities that have experienced great losses worldwide. The dominant seagrass in the meadows of the Pacific coast of North America is Zostera marina. There is evidence that Z. marina has been replaced in some places by the opportunistic seagrass Ruppia maritima with important implications for the trophic connections of local ecosystems. In México, there are few reports on the distribution and loss of seagrass meadows. Here, we report on the importance that R. maritima has gained in three wetlands of northwest México, replacing Z. marina and modifying local trophic networks. We made extensive samplings on Z. marina and R. maritima meadows, recording shoot density and marking their spatial distribution with GPS. We included information on the presence of R. maritima at other wetlands of northwest México from historical reviews and current sampling. R. maritima was recorded in 29 localities, 3 of which are new records. Their shoot density and spatial coverage were highest in late fall and decreased in late spring, while Z. marina meadows increased after the reduction of R. maritima meadows. R. maritima now constitutes a primary food source for green turtles in the sampled wetlands, something unprecedented a few years ago. Improvement of wetland management plans is needed to stop environmental degradation, R. maritima invasion, and the loss of ecosystem functions. © 2010 Senckenberg, Gesellschaft für Naturforschung and Springer. Source

Preece N.D.,James Cook University | Preece N.D.,Charles Darwin University | Preece N.D.,Biome5 Pty Ltd | Lawes M.J.,Charles Darwin University | And 6 more authors.
Forest Ecology and Management | Year: 2015

Few measurements for carbon sequestration, ratio of above-ground to below-ground biomass and wood density exist for young trees. Current allometric models are mostly for mature trees, and few consider trees at the sapling stage. Over four years we monitored the growth rates, from seedling to the sapling stage, of 490 trees (five native species) in environmental plantings, in the Wet Tropics of north-eastern Australia. Our biomass estimates were greater by several orders of magnitude in the first year (6× 10-3Mgha-1 cf. 4× 10-6Mgha-1), and two orders of magnitude less at four years than those derived from the national carbon accounting model (5× 10-1Mgha-1 cf. 13Mgha-1). We destructively sampled 37 young trees to accurately estimate the variation in below-ground and above-ground biomass (AGB) with stem size, and to derive a best fit model for predicting sapling biomass: lnAGB=-5.092+0.786 ln(Diam.base)2Height. Biomass expansion factors for young tree species ranged from 1.71 to 2.44, higher than average for tropical forests. Root:shoot ratios are consistent with mean estimates for mature rainforest. Stem wood densities ranged from 0.444 to 0.683Mgm-3 for the five species measured, which was 6.5% lower than published estimates for three of the species, and 12% and 27% higher for two species. Relative growth rates were faster for species with lower wood density in the first four years, but these species also had the lowest survival over the same period. The findings are significant for a number of reasons. Ecologically, they indicate that young rainforest trees invest more in leaves and branches than in stem growth. From a survival perspective, in the context of rainforest restoration, it is best to invest in species with higher wood densities. From a carbon accounting point of view, refinements to the models used for national carbon accounting are required that include the contribution of the sapling stage. Sapling growth rates were significantly different from those assumed in the national model, requiring growth rates to be increased after four years (as opposed to after 2years in the national model) before reaching an asymptote at some time in the future. This adjustment is essential to enable carbon farmers to judge the time it takes to receive returns from investment. Policies that encourage carbon plantings should take into account that young plantings grow slower than predicted by current national carbon accounting models. © 2015 Elsevier B.V. Source

Rodriguez-Salinas P.,Autonomous University of Baja California Sur | Riosmena-Rodriguez R.,Autonomous University of Baja California Sur | Riosmena-Rodriguez R.,Valle Private University | Hinojosa-Arango G.,The School for Field Studies | Muniz-Salazar R.,Valle Private University
Ecological Engineering | Year: 2010

Zostera marina is the dominant seagrass species in coastal lagoons on the western coast of Baja California Peninsula, and due to its coastal location it is threatened by natural and anthropogenic factors, as is happening in Puerto San Carlos, B.C.S., where a fish cannery unloads its wastewater to the beach. Apparently an extensive intertidal meadow replacement was established by great amounts of green macroalgae. We evaluated the possibility to mitigate the impacts of this cannery with transplants of Z. marina meadow using adult plants. The transplant experiment was made in two different seasons for which two undisturbed donor meadows were chosen: El Cuervo and San Carlitos. The winter one obtained a 30% and in San Carlitos 90% after 13 months and the autumn transplant in San Carlos obtained a 0% of survival after 3 months. The results of these transplant activities were reflected in the shoot density at the end of the experiment (San Carlos was of 482 shoots/m2 and San Carlitos of 818 shoots/m2s and agree with the density of the natural meadows. This experiment shows that it is possible to develop a small-scale seagrass restoration as mitigation for Baja California coastal lagoons which are under severe threat for coastal development. © 2009 Elsevier B.V. All rights reserved. Source

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