MPA

The direct and indirect impacts of the increase in human population, in particular the growing demand for food, as well as various aspects of climate change pose threats to the abundance of parrotfishes (Scarinae), the main coral reef grazers. One way to reduce fishing is by forming marine protected area (MPA). MPAs tend to increase the abundance of marine fish. Well-managed MPA, with effective protection from fishing, could also benefit sex-changing fish populations. The objectives of this research are to assess effects of MPAs on parrotfish abundance and biomass and how do parrotfish abundance and size in the different life phases differ between sites within MPAs and outside MPAs. Fish surveys were conducted in eight Caribbean countries (Antigua, Bonaire, Barbados, Curaçao, Dominican Republic, Jamaica, St. Lucia and St. Vincent and Grenadines (SVG)) using an underwater visual census technique. The differences between parrotfish density and size within and outside MPAs were assessed. Mean parrotfish numerical density was slightly higher at MPA sites than at non-MPA sites but this was not significant. A significant difference was found between parrotfish biomass within and without the MPAs. The abundance biomass comparison (ABC) results showed that out of 33 MPA sites, 79% had a positive index and 21% a negative W-index value. In contrast, only 49% of non-MPA sites surveyed had a positive W-index. Sites within an MPA generally had higher mean parrotfish sizes than those outside the MPA, except for the juvenile phase. The present results reinforce the belief that parrotfish abundance and biomass, which where depleted by fishing, can be increased through applying significant levels of protection. However further research is needed on the effectiveness and duration of protection which are necessary to produce desired levels of improvement in parrotfish abundance, biomass and size.

Consumer-mediated indirect effects at the community level are difficult to demonstrate empirically. Here, we show an explicit indirect effect of overfishing on competition between sponges and reef-building corals from surveys of 69 sites across the Caribbean. Leveraging the large-scale, long-term removal of sponge predators, we selected overfished sites where intensive methods, primarily fish-trapping, have been employed for decades or more, and compared them to sites in remote or marine protected areas (MPAs) with variable levels of enforcement. Sponge-eating fishes (angelfishes and parrotfishes) were counted at each site, and the benthos surveyed, with coral colonies scored for interaction with sponges. Overfished sites had >3 fold more overgrowth of corals by sponges, and mean coral contact with sponges was 25.6%, compared with 12.0% at less-fished sites. Greater contact with corals by sponges at overfished sites was mostly by sponge species palatable to sponge preda- tors. Palatable species have faster rates of growth or reproduction than defended sponge species, which instead make metabolically expensive chemical defenses. These results validate the top-down conceptual model of sponge community ecology for Caribbean reefs, as well as provide an unambiguous justification for MPAs to protect threatened reef-building corals.

An unanticipated outcome of the benthic survey component of this study
was that overfished sites had lower mean macroalgal cover (23.1% vs. 38.1% for less-fished sites), a result that is contrary to prevailing assumptions about seaweed control by herbivorous fishes. Because we did not quantify herbivores for this study, we interpret this result with caution, but suggest that additional large-scale studies comparing intensively overfished and MPA sites are warranted to examine the relative impacts of herbivorous fishes and urchins on Caribbean reefs. 

On Bonaire, we studied the effects of predator abundance and habitat availability on the abundance of the threespot damselfish Stegastes planifrons, a species that creates algal gardens at the expense of live coral cover. Across 21 sites, predator biomass ranged from 12 to 193 g m−2 (mean = 55.1; SD = 49.1) and benthic cover of S. planifrons’ preferred habitat (corals of the Orbicella species complex) ranged from 2.2 to 38.0% (mean = 14.3; SD = 9.6). Across these gradients, the local abundance of S. planifrons was significantly and negatively related to preda- tor biomass, but not to habitat availability. Increased local abundance of S. planifrons corre- sponded to an increasingly larger proportion of coral colonies affected by its ‘farming behavior’, resulting in an increased prevalence of coral disease. Thus, predators indirectly affected the com- position of reef communities around Bonaire by controlling damselfish abundance. Furthermore, the abundance of S. planifrons could not be correlated with its preferred habitat, despite such cor- relations having been observed elsewhere in the Caribbean. 

Abstract:

This report presents the findings of an assessment of capacity building needs for the management of marine protected areas (MPAs) in the Caribbean region. A total of 27 MPA sites in 10 countries and territories were included in the assessment, which is an initiative of NOAA Coral Reef Conservation Program (CRCP) in partnership with the Caribbean Marine Protected Area Management Network and Forum (CaMPAM). A gap analysis of existing MPA capacity documents revealed a great deal of variation in the purpose, geographic scope, methodology, and nature of capacity information that has been collected to date. As such, a broad-based comparison of existing information was challenging and would likely not provide an accurate analysis. Accordingly, for this assessment a new survey tool was developed based on a modified version of an existing NOAA Coral Reef Conservation Program MPA Management Assessment checklist (http://coralreef.noaa.gov/resources/publicationsdata/). This tool, intended to be a guided self-assessment, was used by the consultants in an interview process whereby they read through questions with site managers and then allowed the managers to self-select the answers that they deemed most appropriate for their site’s situation. Each question was followed by a more thorough discussion about why that answer was selected. The regional results demonstrate that the current perceived capacity of sites is greatest in relation to zoning/boundaries, governance, management planning, stakeholder engagement, conflict resolution mechanisms, and outreach and education. Current perceived capacity of sites is lowest in relation to alternative livelihoods, socioeconomic monitoring, and fisheries management.

Priority MPA management capacity needs as identified by managers are:

1. enforcement (10 sites)
2. financing (9 sites)
3. management planning, bio-physical monitoring, socio-economic monitoring (7 sites), and
4. MPA effectiveness evaluation, and outreach and education (6 sites).

Preferred approaches to capacity building at a regional scale are:

1. technical support,
2. training,
3. more staff,
4. learning exchanges, and
5. higher education course.

Individual site results provide more detailed information under the “rationale” narrative sections and can inform users of more specific details of the local situation and capacity strengths, and challenges.