Biosphere Foundation

Big Pine, CA, United States

Biosphere Foundation

Big Pine, CA, United States
SEARCH FILTERS
Time filter
Source Type

Nelson M.,Tropic Ventures Education and Research Foundation | Nelson M.,Santa Fe Institute | Silverstone S.,Biosphere Foundation | Reiss K.C.,University of Florida | And 6 more authors.
Journal of Sustainable Forestry | Year: 2010

The impact on tree and amphibian diversity of line-planting of tropical hardwoods-mahogany (Swietenia macrophylla × S. mahagoni) and mahoe (Hibiscus elatus)-was studied in a secondary subtropical wet forest of Puerto Rico. Common coqui (Eleutherodactylus coqui) and melodious coqui (E. wightmanae) are the most frequent frog species; forest coqui (E. portoricensis) is less abundant. Although relative abundance means were slightly greater in the undisturbed forest and during the wet season, differences were not statistically significant suggesting that line-planting did not significantly affect amphibian diversity. The line-planted areas had a slightly higher, but not statistically significant diversity, richness, and evenness of tree species than the unplanted forest. Multi-response permutation procedure (MRPP) showed statistically significant community composition differences between line-planting and control plot trees (T = -5.89, A =.86; p <.001). But mean similarity among plots in both the line-planted and control plots was relatively low at less than 50% of shared species, indicating high diversity of vegetation in the overall forest area. Canopy cover by tree species greater than 3 cm in dbh was much higher in the undisturbed forest but this difference may be reduced as the young line-planted hardwoods mature. Forest enrichment through line-planting of valuable timber species in secondary subtropical wet forest does not significantly affect tree diversity. © Taylor & Francis Group, LLC.


Dustan P.,College of Charleston | Dustan P.,Biosphere Foundation | Doherty O.,Biosphere Foundation | Pardede S.,Wildlife Conservation Society
PLoS ONE | Year: 2013

Ecological habitats with greater structural complexity contain more species due to increased niche diversity. This is especially apparent on coral reefs where individual coral colonies aggregate to give a reef its morphology, species zonation, and three dimensionality. Structural complexity is classically measured with a reef rugosity index, which is the ratio of a straight line transect to the distance a flexible chain of equal length travels when draped over the reef substrate; yet, other techniques from visual categories to remote sensing have been used to characterize structural complexity at scales from microhabitats to reefscapes. Reef-scale methods either lack quantitative precision or are too time consuming to be routinely practical, while remotely sensed indices are mismatched to the finer scale morphology of coral colonies and reef habitats. In this communication a new digital technique, Digital Reef Rugosity (DRR) is described which utilizes a self-contained water level gauge enabling a diver to quickly and accurately characterize rugosity with non-invasive millimeter scale measurements of coral reef surface height at decimeter intervals along meter scale transects. The precise measurements require very little post-processing and are easily imported into a spreadsheet for statistical analyses and modeling. To assess its applicability we investigated the relationship between DRR and fish community structure at four coral reef sites on Menjangan Island off the northwest corner of Bali, Indonesia and one on mainland Bali to the west of Menjangan Island; our findings show a positive relationship between DRR and fish diversity. Since structural complexity drives key ecological processes on coral reefs, we consider that DRR may become a useful quantitative community-level descriptor to characterize reef complexity. © 2013 Dustan et al.


Nelson M.,Y Ventures | Nelson M.,Santa Fe Institute | Silverstone S.,Biosphere Foundation | Reiss K.C.,University of Florida | And 3 more authors.
Bois et Forets des Tropiques | Year: 2011

Between 1984 and 1990 line planting of a variety of valuable native and introduced broadleaf timber trees, including mahogany, Swietenia macrophylla, and blue mahoe, Talipariti elatum, was carried out on one hundred hectares within a wet tropical secondary forest area of southeastern Puerto Rico. Basal area (BA) annual increment for mahogany indicates for the best 25% of the mahogany trees it will take an estimated 176 years from planting to achieve a mean stand BA of 0.20 m2/tree, which correlates to a mean tree diameter at breast height (DBH) of 50 cm. By contrast, mahoe had a BA increment over three times that of mahogany. In 57 years the mahoe trees will reach a mean stand BA of 0.20 m2/tree. The upper quartile of mahoe trees currently have a mean BA greater than 0.10 m2/tree and can already be selectively harvested. In trials with native species, Coccoloba pubescen, Calophyllum brasiliense, and Cedrela odorata had the greatest percent increase in height with favorable survival rates, but longer term studies are needed. Line planting within secondary forests such as those at Las Casas can increase the value of secondary forests, providing both sustainable timber production for profit and preservation of biodiversity and the other environmental advantages of maintenance of forests. Enrichment and management of secondary forests should be explored as a promising approach to sustainable forestry.


Priyadarshana T.,Ruhuna University | Randage S.M.,Ruhuna University | Alling A.,Biosphere Foundation | Calderan S.,Canal House | And 3 more authors.
Regional Studies in Marine Science | Year: 2016

Surveys were conducted off the southern coast of Sri Lanka in 2014 and 2015 to investigate the distribution patterns of blue whales (Balaenoptera musculus spp.) in relation to current shipping lanes, and further offshore. There have been several reported ship strikes of blue whales in this area and the IWC Scientific Committee has recognised the potential for ship strikes to have population level impacts on blue whales in the northern Indian Ocean. A total of 3268 km of visual survey effort was conducted on 35 survey days along north-south transects between 5°28′N and 5°53′N. These data were used to model patterns of whale density. The highest densities of blue whales were observed in the current shipping lanes, peaking at an average of 0.1 individuals km-2 along the westbound shipping lane. Automatic Identification System transmissions received by satellite were used to estimate shipping density. Between 80°30′E and 81°E, the peak mean shipping density in the westbound lane of the Traffic Separation Scheme was 1090 km-1 year-1 and in the eastbound lane 810 km-1 year-1. These high densities of whales combined with one of the busiest shipping routes in the world suggest a severe risk of ship strikes. Previous data on blue whale distribution and coastal upwellings indicate consistent and predictable patterns of whale distribution, suggesting there is considerable potential for effective measures to keep ships and whales apart. For example, data from this study would suggest risk could be reduced by 95% if shipping were to transit 15 nm further south than currently. © 2015 Elsevier B.V. All rights reserved.


Milner C.,Biosphere Foundation | Currier K.,Biosphere Foundation | Currier K.,University of California at Santa Barbara | Kopcho B.,Biosphere Foundation | Alling A.,Biosphere Foundation
Atoll Research Bulletin | Year: 2013

The coral reefs surrounding Pulau Durai (located in the northwest of Indonesia in the Anambas Islands, South China Sea) were surveyed from 22 June to 5 July 2011 to provide baseline data on their biotic composition and condition. At each of four sites around the island, point intercept methodology over two 50 m transects yielded an average benthic cover of 26% live hard coral. The maximum live hard coral cover observed was 47% on the northern side of the island where fishing boats anchor overnight to seek shelter from the southwest monsoon. The minimum of 3% live hard coral was observed on the west side, which is the inhabited area of the island and where there is the greatest amount of anthropogenic activity. A total of 38 hard coral genera and 115 fish species were recorded across all transects. The average biomass of fish per transect was 2135.5 kg/ha and the populations were mostly comprised of herbivores which correlated with the abundance of dead coral, algae overgrowth, and lack of predator fish. Crown-of-thorns starfish (Acanthaster planci) were present at all sites with a maximum of 15 individuals sighted on both the North Shallow and South Shallow transects. In general, damage from anchors and destructive fishing practices have gravely impacted Pulau Durai's reefs in the past. Present threats include continued anchoring, over-fishing and a current infestation of crown-of-thorns starfish, which are negatively affecting the remaining health and abundance of living coral. Pulau Durai and its neighbouring island, Pulau Pahat, were declared a marine protected area in July 2011. Given the depleted state of this reef, it will be imperative to establish a "no-take" fishing area to restore the fish populations, ban anchoring on the reef to stop the destruction of coral, and if possible, remove the crown-of-thorns starfish.


Priyadarshana T.,Ruhuna University | Randage S.M.,Ruhuna University | Alling A.,Biosphere Foundation | Calderan S.,Canal House | And 3 more authors.
Regional Studies in Marine Science | Year: 2015

Surveys were conducted off the southern coast of Sri Lanka in 2014 and 2015 to investigate the distribution patterns of blue whales (Balaenoptera musculus spp.) in relation to current shipping lanes, and further offshore. There have been several reported ship strikes of blue whales in this area and the IWC Scientific Committee has recognised the potential for ship strikes to have population level impacts on blue whales in the northern Indian Ocean. A total of 3268km of visual survey effort was conducted on 35 survey days along north-south transects between 5°28'N and 5°53'N. These data were used to model patterns of whale density. The highest densities of blue whales were observed in the current shipping lanes, peaking at an average of 0.1 individuals km-2 along the westbound shipping lane. Automatic Identification System transmissions received by satellite were used to estimate shipping density. Between 80°30'E and 81°E, the peak mean shipping density in the westbound lane of the Traffic Separation Scheme was 1090km-1 year-1 and in the eastbound lane 810km-1 year-1. These high densities of whales combined with one of the busiest shipping routes in the world suggest a severe risk of ship strikes. Previous data on blue whale distribution and coastal upwellings indicate consistent and predictable patterns of whale distribution, suggesting there is considerable potential for effective measures to keep ships and whales apart. For example, data from this study would suggest risk could be reduced by 95% if shipping were to transit 15 nm further south than currently. © 2015 Elsevier B.V.


Randage S.M.,Captain | Randage S.M.,Ruhuna University | Alling A.,Biosphere Foundation | Currier K.,Biosphere Foundation | And 2 more authors.
Journal of Cetacean Research and Management | Year: 2014

A population of blue whales is resident off the southern coast of Sri Lanka and has been observed year-round by the crew of a whalewatching vessel, Raja & the Whales, a few miles south of Mirissa Harbour. Over the course of three years (1 December 2009 to 30 November 2012), a total of 485 blue whale sightings were reported with an average of 4.56 individuals observed per sighting. This number does not represent the total number of individuals seen because repeat sightings were highly probable. Calves were observed during the northeast monsoon. Sightings were confined to an area of about 200 n.miles that is bisected by a heavily trafficked shipping lane. Much of this area is characterised by submarine canyons and sloping bathymetry, which contributes to monsoonal seasons of high productivity and upwelling suitable for feeding whales. While the numbers of injuries and fatalities due to ship strikes are not known, four dead blue whales were observed along the southern coast over the course of five months (1 January to 31 May 2014). It is of great urgency to understand the identity and size of this population, reduce ship strikes and address all issues threatening this population in order to arrive at possible mitigation measures for its protection.

Loading Biosphere Foundation collaborators
Loading Biosphere Foundation collaborators