| Marine reserve establishment often leads to increases in higher order consumers. I hypothesized that variation in habitat architecture can explain why marine reserve are not uniformly effective. Within the Upper Florida Keys National Marine Sanctuary, point-counts were used to assess reef fishes in replicated “no-take” zones and on a fished reef. The chain method and video were used to characterize the habitat architecture. Once architecture differences were statistically controlled, benefits of marine protection were limited to snappers and small herbivorous fishes. Available shelter best explained the variation in the fish communities, and landscape geometry influenced fish diversity and the density of snappers. The degree to which smaller consumers foraged across habitat boundaries was assessed by sampling seagrass, coring for invertebrates, and tethering brittlestars. The factors of time, distance from reef edge, and protection status all influenced cross-habitat energy exchange. These results indicated that available shelter, and to a lesser extent landscape geometry, confounded the ability to detect recovery of higher order consumers within marine reserves. Therefore, further consideration needs to be given to habitat architecture when studying higher order consumers within marine reserves. |
