Grimsditsch et al Pemba Resilience Survey 2009 low res

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Detailed Results Density 250m2 200 180 160 140 120 100 80 60 40 20 0 Misali Fundo Outer Simba Mandela Kokota Paradise Manta Njao Gap The Hole Swiss Grazers/detritivores Small excavators Scrapers Large excavators Grazers Brow sers Msuka Bay Fundo Lagoon Fundo Inner Herbivorous Fish Densities This bar graph shows only densities for herbivorous functional groups. Misali, the notake zone, has the highest fish densities, and especially high numbers of browsers (mostly Kyphosidae – chubs). It also has higher numbers of small excavators (Scaridae – certain species of parrotfish) than other sites, so these groups seem to be recovering well with the no-take zone. Fundo Outer also has high fish densities compared to other sites. However, this is mostly driven by higher numbers of Lutjanidae (snappers) and Lethrinidae (emperors) that are both predators. Fundo Outer also has higher densities of scrapers (Scaridae – certain species of parrotfish) than other sites probably due to its larger distance distance from shore and consequent lower fishing pressure. Msuka Bay, Fundo Lagoon and Fundo Inner have the lowest fish densities. Msuka Bay Fundo Lagoon Transform: Square root Resemblance: S17 Bray Curtis similarity 2D Stress: 0.11 Similarity The Hole 80 Manta Kokota Fundo Outer Mandela Njao Gap Simba Paradise Misali Swiss Sites and fish community composition In the Multi-Dimensional Scaling, Misali is an outlier due to the high densities of browsers, while Fundo Lagoon is an outlier due to overall low densities of fish, although relatively high densities of scrapers. Msuka Bay and Fundo Inner form an outlying group due to their low fish densities. Fundo Inner Transform: Square root Resemblance: S17 Bray Curtis similarity 2D Stress: 0.11 Browsers Browser Density in Misali Msuka Bay Fundo Lagoon The Hole Manta Kokota Mandela Njao Gap Paradise Fundo Outer Simba Misali 20 80 140 200 The two bubble plots show the high densities of browsers (top plot) and small excavators (bottom plot) that distinguish Misali, the notake zone. The family making up the most number of browsers in Misali are Kyphosidae, or chubs. Swiss Fundo Inner Fundo Lagoon The Hole Manta Kokota Mandela Transform: Square root Resemblance: S17 Bray Curtis similarity 2D Stress: 0.11 Small excavators Fundo Outer 0.7 2.8 Msuka Bay Njao Gap Paradise Simba Misali 4.9 7 Swiss Fundo Inner 29
Detailed Results Individuals per 250m2 650 600 550 500 450 400 350 300 250 200 150 100 50 0 1 to 10 11 to 20 21 to 30 31 to 40 Other groups Grazers Scrapers Browsers Grazers/detritivores Small excavators Large excavators 41 to 50 Fish abundance by size class Another very strong indication of overfishing is the fact that hardly any large fish were seen during the surveys. The bar graph shows that the vast majority of fish seen were 40 cm seen during the entire survey were 1 grouper at Njao Gap, 1 grouper at Fundo Inner and 2 parrotfish at Misali. This is clearly an overfished coral reef with serious implications for future resilience. Misali Fundo Outer Simba Swiss Paradise Kokota Mandela Njao Gap Transform: Square root Resemblance: S17 Bray Curtis similarity Fundo Inner The Hole Manta Fundo Lagoon 2D Stress: 0.05 Msuka Bay Similarity 80 Site Similarities in Fish Size Class Distributions The Multi-Dimensional Scaling of fish size class distributions shows that Misali and Fundo Outer are outliers due to the higher number of larger bodied fish present. In Misali fish in the 21-30 cm size class were mostly Kyphosidae (chubs), Carangidae (jacks), Scaridae (parrotfish) and Lethrinidae (emperors). In Fundo Outer fish in that size class were mostly Lethrinidae. Therefore, as well as having higher numbers of larger fish, Misali has a higher diversity of large fish. Msuka Bay stands out as an outlier due to the low fish densities. 30
Page 1 and 2: Coral Reef Resilience Assessment of
Page 3 and 4: Coral Reef Resilience Assessment of
Page 6 and 7: Executive Summary 1 Executive Summa
Page 8 and 9: Executive Summary 2. Tackle the ove
Page 10 and 11: The Study coral colony and coral co
Page 12 and 13: The Study Table 2.1. Sites surveyed
Page 14 and 15: The Study 7. Resilience indicators
Page 16 and 17: Major Findings on the site that is
Page 18 and 19: Major Findings rabbitfish, angelfis
Page 20 and 21: Major Findings 2. Tackle the overfi
Page 22 and 23: Detailed Results 4 Detailed Results
Page 24 and 25: Detailed Results % coral colonies 1
Page 26 and 27: Detailed Results 4.2 Coral communit
Page 28 and 29: Detailed Results 4.3 Coral populati
Page 30 and 31: Detailed Results Moderate Faviid Su
Page 32 and 33: Detailed Results 4.4 Crown-of-thorn
Page 36 and 37: Detailed Results 4.6 Resilience ind
Page 38 and 39: Detailed Results Influence of resil
Page 40 and 41: Detailed Results Fundo Lagoon Msuka
Page 42: INTERNATIONAL UNION FOR CONSERVATIO

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