Latitudinal gradients affect coral community change.

<p>(A) Total coral cover and (B) acroporid cover are declining faster in the southern WIO (<15°S) than the northern WIO (>15°S). Note: Latitude is shown as ‘north’ (open circles, dashed line) and ‘south’ groups (filled circles, solid line) to illustrate the significant interaction between year x latitude; latitude is a continuous factor is all analyses. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0093385#pone-0093385-t002" target="_blank">Table 2</a> for model results.</p

Top mixed-effects hierarchical linear models for Western Indian Ocean coral communities.

<p>The original model for each response contained all main effects and their two-way interactions. Geography indicates mainland - island environments. The best-fit top model was reached after step-wise backwards elimination of non-significant predictors; significant parameters for each final model are highlighted in bold.</p

The preferred minimum fish size limit.

<p>The cumulative frequency of the preferred minimum fish size limit is plotted for respondents from Kigombe, Mwarongo and Ushongo villages.</p

The collaborative management areas (CMAs), year of establishment, the reefs within the CMAs and the year of closure of reefs within the CMA in the Tanga Region (a), and the physical characteristics of the study sites (b).

<p>The study sites and the villages adjacent to these sties are shown in bold.</p

Regional patterns of coral cover and community composition.

<p>Coral communities vary across (A) latitude, (B) geography of mainland or island locations, and (C) fisheries management. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0093385#pone-0093385-t002" target="_blank">Table 2</a> for model results. In (A), lines indicate significant relationships between coral abundance and latitude. For (B) and (C), asterisks indicate significant differences between groups. Boxplots show median and quartiles, and dots indicate outliers.</p

What Happens after Conservation and Management Donors Leave? A Before and After Study of Coral Reef Ecology and Stakeholder Perceptions of Management Benefits

<div><p>The coral reefs of Tanga, Tanzania were recognized as a national conservation priority in the early 1970s, but the lack of a management response led to damage by dynamite, beach seines, and high numbers of fishers until the mid 1990s. Subsequently, an Irish Aid funded IUCN Eastern Africa program operated from 1994 to mid 2007 to implement increased management aimed at reducing these impacts. The main effects of this management were to establish collaborative management areas, reduce dynamite and seine net fishing, and establish small community fisheries closures beginning in 1996. The ecology of the coral reefs was studied just prior to the initiation of this management in 1996, during, 2004, and a few years after the project ended in 2010. The perceptions of resource users towards management options were evaluated in 2010. The ecological studies indicated that the biomass of fish rose continuously during this period from 260 to 770 kg/ha but the small closures were no different from the non-closure areas. The benthic community studies indicate stability in the coral cover and community composition and an increase in coralline algae and topographic complexity over time. The lack of change in the coral community suggests resilience to various disturbances including fisheries management and the warm temperature anomaly of 1998. These results indicate that some aspects of the management program had been ecologically successful even after the donor program ended. Moreover, the increased compliance with seine net use and dynamite restrictions were the most likely factors causing this increase in fish biomass and not the closures. Resource users interviewed in 2010 were supportive of gear restrictions but there was considerable between-community disagreement over the value of specific restrictions. The social-ecological results suggest that increased compliance with gear restrictions is largely responsible for the improvements in reef ecology and is a high priority for future management programs.</p></div

Results of a forward stepwise regression analyses evaluating the association between socio-demographic and management restrictions variables.

<p>Results presented are (a) various management restrictions (b) communities, all fishers pooled.</p

The biomass of eleven common finfish families (mean ± SD, kg/ha) and the total finfish biomass at all reefs sampled in 2010 and the Kruskal-Wallis comparison of finfish families between sites.

<p>The biomass of eleven common finfish families (mean ± SD, kg/ha) and the total finfish biomass at all reefs sampled in 2010 and the Kruskal-Wallis comparison of finfish families between sites.</p

The changes in the biomass of finfish in different size classes.

<p>The biomass (mean kg/ha) was estimated for eleven common finfish families sampled in 1996, 2004 and 2010.</p

Map of the Tanga, Tanzania study location.

<p>(a) the Tanga coastline and collaborative management areas (CMA) of the coastal zone management project and (b) satellite image of reefs and study sites in the Mtangata and Boza-Sange CMA.</p