Challenges of a transition to a sustainably managed shrimp culture agro-ecosystem in the Mahakam delta,East Kalimantan,Indonesia

Around 1990, when in other countries mangrove protection took off, massive conversion of mangrove forest into shrimp ponds started in the Mahakam delta. To identify constraints to and options for sustainable management we analysed institutions and constraints with stakeholders. In 3 sites we used participatory tools and a complementary survey to assess the livelihood framework. Since 1970, ponds for shrimp farming gradually replaced 75% of mangrove forested area. After 2004, recovery of mangrove took off, as, mainly due to low shrimp yields, ponds were abandoned. In 2008, 54% of the delta was dedicated to ponds for shrimp production. Around 80% of livelihood activities of pond-farmers, pond caretakers, and fishermen was related to mangroves. The involvement of men and women in these activities varied between sites and types. Poor households depended more on mangroves. Most activities resulted in seasonal income peaks; only a few activities resulted in a full daily livelihood. Ponds, on the other hand, provide 50% of households’ livelihood, but this remains vulnerable in the context of the risky shrimp production. Skewed land holding, unequal sharing of benefits, competing claims and vested interests of stakeholders pose a great challenge to a transition to a more sustainable use of the mangrove area. In particular, ponds located on peat soils are non-sustainable and would require full restoration into mangrove; ponds on other soils could best be transformed into a mixed mangrove-pond system using a ‘green-water’ technology.     

Life history of the silvertip shark Carcharhinus albimarginatus from Papua New Guinea

Coral Reefs - Growth and maturity of the silvertip shark Carcharhinus albimarginatus from Papua New Guinea were estimated to form the basis of future population assessments. Samples were collected...     

Progress toward Global Reduction in Under-Five Mortality: A Bootstrap Analysis of Uncertainty in Millennium Development Goal 4 Estimates

Background

Millennium Development Goal 4 calls for an annual rate of reduction (ARR) of the under-five mortality rate (U5MR) of 4.4% between 1990 and 2015. Progress is measured through the point estimates of the United Nations Inter-agency Group for Child Mortality Estimation (UN IGME). To facilitate evidence-based conclusions about progress toward the goal, we assessed the uncertainty in the estimates arising from sampling errors and biases in data series and the inferior quality of specific data series.

Methods and Findings

We implemented a bootstrap procedure to construct 90% uncertainty intervals (UIs) for the U5MR and ARR to complement the UN IGME estimates. We constructed the bounds for all countries without a generalized HIV epidemic, where a standard estimation approach is carried out (174 countries). In the bootstrap procedure, potential biases in levels and trends of data series of different source types were accounted for. There is considerable uncertainty about the U5MR, particularly for high mortality countries and in recent years. Among 86 countries with a U5MR of at least 40 deaths per 1,000 live births in 1990, the median width of the UI, relative to the U5MR level, was 19% for 1990 and 48% for 2011, with the increase in uncertainty due to more limited data availability. The median absolute width of the 90% UI for the ARR from 1990 to 2011 was 2.2%. Although the ARR point estimate for all high mortality countries was greater than zero, for eight of them uncertainty included the possibility of no improvement between 1990 and 2011. For 13 countries, it is deemed likely that the ARR from 1990 to 2011 exceeded 4.4%.

Conclusions

In light of the upcoming evaluation of Millennium Development Goal 4 in 2015, uncertainty assessments need to be taken into account to avoid unwarranted conclusions about countries'' progress based on limited data. Please see later in the article for the Editors'' Summary     

Phylogeography of the Sponge Suberites diversicolor in Indonesia: Insights into the Evolution of Marine Lake Populations

The existence of multiple independently derived populations in landlocked marine lakes provides an opportunity for fundamental research into the role of isolation in population divergence and speciation in marine taxa. Marine lakes are landlocked water bodies that maintain a marine character through narrow submarine connections to the sea and could be regarded as the marine equivalents of terrestrial islands. The sponge Suberites diversicolor (Porifera: Demospongiae: Suberitidae) is typical of marine lake habitats in the Indo-Australian Archipelago. Four molecular markers (two mitochondrial and two nuclear) were employed to study genetic structure of populations within and between marine lakes in Indonesia and three coastal locations in Indonesia, Singapore and Australia. Within populations of S. diversicolor two strongly divergent lineages (A & B) (COI: p = 0.4% and ITS: p = 7.3%) were found, that may constitute cryptic species. Lineage A only occurred in Kakaban lake (East Kalimantan), while lineage B was present in all sampled populations. Within lineage B, we found low levels of genetic diversity in lakes, though there was spatial genetic population structuring. The Australian population is genetically differentiated from the Indonesian populations. Within Indonesia we did not record an East-West barrier, which has frequently been reported for other marine invertebrates. Kakaban lake is the largest and most isolated marine lake in Indonesia and contains the highest genetic diversity with genetic variants not observed elsewhere. Kakaban lake may be an area where multiple putative refugia populations have come into secondary contact, resulting in high levels of genetic diversity and a high number of endemic species.