Modern and foss11 chemoautotrophlc communitiessupported by organ~c-nch whale skeletons have been reported flom the bathyal-abyssal seafloor I n the eastern and western North Paciflc Based on studies w~t h the research submersible ALVIN, w e describe here general habitat charactenstics and macro-and megafaunal community structure of one such cominunity estimated to be > 4 yr old associated with an 18 m baleanoptend skeleton at 1240 m in the Santa Catalina Basln (SCB) off California, USA The vls~ble remains of the whale in 1988-91 conslsted of partially burled skeletal inaterlal (prlmarlly vertebrae and the head complex) with a plan area of approx~mately 7 9 m 2 White and yellow mats of sulfur-ox~dizlng bacteria covered many of the bone surfaces yleldlng a n estimated mat area of at least 4 0 m q o n e collections Indicated a total attached macrofaunal community of at least 12490 ~n d~v~d u a l s dlstnbuted among 2 4 3 specles, with 6 species w~t h population sizes of > 1000 lndlvlduals Megafauna associated wlth the skeleton conslsted prlinarlly of the vesicomy~d clam Veslcomya cf gigas, w~t h an estimated populat~on slze of 400 to 800 l n d~v~d u a l sThe whale-skeleton fauna1 community was taxonomically dlstinct from that of the surrounding SCB, with >97'% of its individuals belonging to specles very rare or absent in background sediments The whale-skeleton assemblage exhlblted strong taxonomic and functional affin~lles to other deep-sea reduclng habltats ( e g hydrothermal vents and cold seeps), marked by a prominence of veslcomyld clams and myt111d mussels with sulfide-oxld~zing, chemoautotrophic bacterial endosymbionts In addition, 5 of the whalefall specles (Pyropelta corymba, P musalca, Bathykurjla guaymasensls, Idasola washlnytonla and Coccuhna c r a l g s m t h~) also appear to occur at Juan d e Fuca and/or Guaymas Basln hydrothermal vents, desplte geographic separation of -1800 kin We conclude that whale falls may nurture substantial sulfide-dependent communities at the deep-sea floor, and that some species may be dispelsing to hydrothermal vents from whale-fall habitat islands

This study was designed to establish whether populations of fish species important in the catches of rock and surf anglers increased following the proclamation of the De Hoop Marine Reserve on the southern coast of South Africa Catch per unit effort (CPUE) and size frequency distributions of angling species were monitored approximately monthly by angling from the shore at 2 sites in the reserve. At one site sampling commenced 2 yr before the reserve was established and continued 4.5 yr thereafter, allowing comparisons of periods of exploitation and protection. The other site had a long history of minimal exploitation and data collected there 2 . 5 to 4.5 yr after complete protection was considered to represent an unexplolted condition. Ten species accounted for 99% of the catch. Following establishment of the reserve. CPUE increased for 6 of these (galjoen Coracinus capensis, dassie Diplodus sargus, wildeperd D. cervinus, white steenbras Lithognathus lithognathus, Cape stumpnose Rhabdosargus holubi and musselcracker Sparodon durbanensis) The catch rates of 2 species (C. capensis and D. sargus) improved 4 to 5 fold within 2 yr of protection and remained at these high levels, which were similar to the unexploited catch rates. Recoveries were slower amongst the other 4 species, their catch rates reaching 30 to 60% of the unexploited level after 2 . 5 to 4.5 yr of protection This study provides evidence of general stock recoveries of exploited fish species in a shallow marine habitat following protection within a marine reserve.

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