Time filter

Source Type

Dendy J.,Coral Reef Research Foundation | Dendy J.,U.S. Department of Agriculture | Cordell S.,U.S. Department of Agriculture | Giardina C.P.,U.S. Department of Agriculture | And 3 more authors.
Restoration Ecology | Year: 2015

To be successful, prescriptions for tropical forest restoration should facilitate natural recovery while also being easy to implement and inexpensive. In the Lake Ngardok Nature Reserve, Palau, we monitored native forest patches (4-275 m2) over 3 years to assess the influence of several low-cost restoration methods on patch expansion, growth of naturally established tree saplings, density of naturally establishing tree seedlings, growth of planted tree seedlings, flower and fruit production, and bird and flying fox visitations. Treatments included fertilization, trimming of surrounding herbaceous vegetation, mulching of patch perimeters, and planting native tree seedlings. Fertilized patches expanded faster and were associated with higher growth rates of perimeter saplings, higher fruit and flower production and growth of adjacent planted Acacia auriculiformis trees. Trimming perimeter vegetation led to higher tree seedling densities and species diversity, but both trimming and fertilizer effects on patch perimeter measures decreased over time. Pterocarpus indicus, a high value native legume, was the fastest growing planted tree species. The most common visitors were small, omnivorous, predominately endemic bird species. Visitations to fertilized patches were more frequent than to non-fertilized patches. The strongest predictors of visitation frequency were patch area, mean number of total fruits, and mean height of nearest neighboring trees. We conclude that forest succession can be accelerated by applying small amounts of fertilizer (approximately 22.5 g/m2 per application) to enhance tree growth and increase visitation rates of native pollinators and dispersers. © 2015 Society for Ecological Restoration.

The humphead wrasse Cheilinus undulatus formed resident spawning aggregations daily after high tide at specific locations along the seaward edge of the Palau barrier reef. The location and extent of one aggregation site remained consistent for 6 years with no physical features distinguishing it from adjacent areas. Spawning was documented most months and probably occurred year round with possible seasonal and lunar variation. Spawning males arrived first at the site, followed by females and potentially small primary males. The aggregation female to male sex ratio was estimated to be between 6:1 and 10:1. A maximum of 15 males and 100-150 females were observed at the site. A male courtship posture with the anal fin pointed, the caudal fin folded down and the dorsal fin folded against the body was maintained while swimming a few metres off the bottom in view of females. When ready to spawn females rose up as the posturing male passed and the pair released gametes in a relatively sedate fashion near the surface along the shelf break. No attempted predation on spawning adults was seen. Egg predation after spawning was uncommon. On days with early to mid-day high tides the spawning period started 2·0-2·5 h after high tide when the speed of lagoon-ocean tidal currents peaked and lasted c. 1 h. On days with later afternoon high tides, spawning occurred sooner after high tide and before current speeds peaked. Other fishes with planktonic eggs spawned at the site as pairs or small groups in a rough succession after high tide with C. undulatus, the last species to spawn. © 2010 The Author. Journal compilation © 2010 The Fisheries Society of the British Isles.

Colin P.L.,Coral Reef Research Foundation | Sadovy de Mitcheson Y.,University of Hong Kong | Donaldson T.J.,University of Guam
Estuarine, Coastal and Shelf Science | Year: 2013

Golbuu and Friedlander (2011, Estuar. Coast. Shelf Sci. 92:223) used faulty methods, improper interpretation of historical data, and assumptions of little or no validity to conclude that despite protected status spawning aggregations of three groupers in Palau, western Caroline Islands declined between 1995-96 and 2005-06. Alternate survey methods indicated no drastic declines in these aggregations over the same period. Golbuu and Friedlander (2011) failed to document the overall distribution of fishes in their aggregations, used poorly-located inadequate transects to sample the overall aggregation area, and did not identify and sample peak aggregations days. The use of visual length estimates as the basis for biomass values may introduce errors. Comparison of aggregation persistence between reference (" fished out" ) and protected sites is not possible because equivalent protected and exploited sites are not available. Different species at multi-species spawning aggregation sites commonly occupy somewhat discrete locations, with the densest concentrations (core areas) of one often being separated from those for another. There is usually a single peak day each month of a lunar-based aggregation, but it requires multiple days data collection to determine that peak. The shortcomings identified provide important lessons for the study of fish spawning aggregations and signal caution about the incomplete documentation of sampling methodology. Overly simplistic aggregation sampling methodologies may be superficially credible, but are not reflective of a complicated reality. Monitoring needs to produce a definitive repeatable baseline against which data can be gathered authoritatively in the future. © 2011 Elsevier Ltd.

Brand U.,Brock University | Azmy K.,Memorial University of Newfoundland | Griesshaber E.,Ludwig Maximilians University of Munich | Bitner M.A.,Polish Academy of Sciences | And 4 more authors.
Chemical Geology | Year: 2015

We examined a large number of modern, shallow-water articulated brachiopods representing the orders Terebratulida, Rhynchonellida, Thecideida and one inarticulated brachiopod of the order Craniida from polar to tropical regions for their carbon isotope compositions. Based on our detailed investigation, we recommend avoiding fast growth areas such as the youngest shell increments; in addition, the primary layer and transition zone calcites of brachiopods must be avoided because they are in carbon and oxygen isotope disequilibrium with ambient seawater. After adjusting isotope compositions for the Mg effect, we observed no significant difference (p>0.05) in δ13C values between dorsal and ventral valves of our articulated brachiopods. Using the calcite-bicarbonate enrichment factor (ε) in conjunction with δ13C values of dissolved inorganic carbon of habitat seawater, we conclude that modern shallow-water articulated and some inarticulated brachiopods incorporate oxygen (Brand et al., 2013) and carbon isotopes into shell calcite of secondary and/or tertiary layers in apparent equilibrium with ambient seawater. Within the general concept of equilibrium incorporation, with seawater, shell δ13C values are an excellent recorder of local/global seawater environments and water mass circulation. Thus, application of the Mg-effect permits brachiopods to be an extremely powerful archive, and δ13C values more precise proxy and tracer of past changes in marine productivity, evolution of seawater carbon chemistry and variation in the global carbon cycle. © 2015 Elsevier B.V.

In the tropical western North Atlantic the goby genus Elacatinus has at least 25 species which can be separated into five eco-morphological suites. Within a suite, geographic distributions of species are usually mutually exclusive. Last reviewed in 1975 numerous published misidentifications have confused the zoogeography in addition to new taxa having been added. The species and their distributions are reviewed, corrected and updated to prepare for an analysis of their zoogeography relative to mechanisms of connectivity through ocean currents. Copyright © 2010 Magnolia Press.

Discover hidden collaborations