Coral reefs have emerged as one of the ecosystems most vulnerable to climate variation and change. While the contribution of a warming climate to the loss of live coral cover has been well documented across large spatial and temporal scales, the associated effects on fish have not. Here, we respond to recent and repeated calls to assess the importance of local management in conserving coral reefs in the context of global climate change. Such information is important, as coral reef fish assemblages are the most species dense vertebrate communities on earth, contributing critical ecosystem functions and providing crucial ecosystem services to human societies in tropical countries. Our assessment of the impacts of the 1998 mass bleaching event on coral cover, reef structural complexity, and reef associated fishes spans 7 countries, 66 sites and 26 degrees of latitude in the Indian Ocean. Using Bayesian meta-analysis we show that changes in the size structure, diversity and trophic composition of the reef fish community have followed coral declines. Although the ocean scale integrity of these coral reef ecosystems has been lost, it is positive to see the effects are spatially variable at multiple scales, with impacts and vulnerability affected by geography but not management regime. Existing no-take marine protected areas still support high biomass of fish, however they had no positive affect on the ecosystem response to large-scale disturbance. This suggests a need for future conservation and management efforts to identify and protect regional refugia, which should be integrated into existing management frameworks and combined with policies to improve system-wide resilience to climate variation and change.

Endo-␤-1,4-xylanases (xylanases), which cleave ␤-1,4 glycosidic bonds in the xylan backbone, are important components of the repertoire of enzymes that catalyze plant cell wall degradation. The mechanism by which these enzymes are able to hydrolyze a range of decorated xylans remains unclear. Here we reveal the threedimensional structure, determined by x-ray crystallography, and the catalytic properties of the Cellvibrio mixtus enzyme Xyn10B (CmXyn10B), the most active GH10 xylanase described to date. The crystal structure of the enzyme in complex with xylopentaose reveals that at the ؉1 subsite the xylose moiety is sandwiched between hydrophobic residues, which is likely to mediate tighter binding than in other GH10 xylanases. The crystal structure of the xylanase in complex with a range of decorated xylooligosaccharides reveals how this enzyme is able to hydrolyze substituted xylan. Solvent exposure of the O-2 groups of xylose at the ؉4, ؉3, ؉1, and ؊3 subsites may allow accommodation of the ␣-1,2-linked 4-O-methyl-D-glucuronic acid side chain in glucuronoxylan at these locations. Furthermore, the uronic acid makes hydrogen bonds and hydrophobic interactions with the enzyme at the ؉1 subsite, indicating that the sugar decorations in glucuronoxylan are targeted to this proximal aglycone binding site. Accommodation of 3-linked L-arabinofuranoside decorations is observed in the ؊2 subsite and could, most likely, be tolerated when bound to xylosides in ؊3 and ؉4. A notable feature of the binding mode of decorated substrates is the way in which the subsite specificities are tailored both to prevent the formation of "dead-end" reaction products and to facilitate synergy with the xylan degradation-accessory enzymes such as ␣-glucuronidase. The data described in this report and in the accompanying paper (Fujimoto, Z., Kaneko, S., Kuno, A., Kobayashi, H., Kusakabe, I., and Mizuno, H. (2004) J. Biol. Chem. 279, 9606 -9614) indicate that the complementarity in the binding of decorated substrates between the glycone and aglycone regions appears to be a conserved feature of GH10 xylanases.

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Supplemental methods Geomorphological data: Multibeam bathymetric data were collected during NOAA's Reef Assessment and Monitoring Program (RAMP) surveys of Palmyra aboard the NOAA Ship Hi´ialakai and the survey launch R/V AHI (Acoustic Habitat Investigator). The Hi´ialakai is equipped with two Kongsberg/Simrad multibeam sonars: a 30 kHz EM300 with mapping capability from ~100 to 3000+ m and a 300 kHz EM3002D with mapping capability from ~5 to 150 m. The R/V AHI has a 240 kHz Reson 8101ER with mapping capability from ~5 to 300 m. Both vessels have Applanix POS/MV motion sensors, which provide navigation and highly accurate readings of the vessel motion in all axes. Data were post-processed by the Pacific Islands Benthic Habitat Mapping Center (http://www.soest.hawaii.edu/pibhmc). IKONOS satellite imagery was used to create "estimated depths" and filled bathymetric gaps that existed within the 0-25 m depth range (Lyzenga 1985). Surface whitewash in the IKONOS image resulted in the identification of false depth estimates at select locations around Palmyra. These areas were manually removed and filled using a nearest neighbor interpolation method in ArcGIS Spatial Analyst (v 10.1, http://www.esri.com), resulting in a seamless 5 m bathymetry data set. Waves: We incorporated a coupled hydrodynamic model developed by Delft Hydraulics (Delft3D; http://oss.deltares.nl/web/delft3d) to provide a high-resolution, nearshore spatial assessment of wave forcing at Palmyra. Each of the three models were run on a 7 x 20 km rectangular grid with a 50 m resolution and a 1 min time step over a 12 h period, with a coupling interval of 1 h between wave and current models. Water level (0.3 m) and winds (5 m s-1 from the northeast) were held constant over the model runs, representing average tidal and wind conditions for Palmyra. In the model, wave-and current-induced bed shear stress (BSS) were combined following parameterizations from (Soulsby et al. 1993) that account for the enhancement of BSS due to non-linear wave-current interactions. Following both numerical models and observations in similar coral reef environments, the wave friction factor was set to 0.3 (Péquignet et al. 2011, Van Dongeren et al. 2013), and the current friction factor was set to 0.2 (Hench et al. 2008, Lowe et al. 2009, Van Dongeren et al. 2013). The numerical model was run under all three wave regimes (i.e. northwest swell, northeast trade wind swell, and south swell) Palmyra is exposed to and combined to calculate an annual average maximum, mean, and range in H s , t p , and BSS.

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