. Annual report - Western Society of Malacologists. Mollusks; Mollusks. Figure 2. Brachyuran crab prevalence on the urchin spines (E. galapagensis). The HF sites showed significantly greater average values of prevalence of infection compared to the LF sites in the Galapagos archipelago. Discussion The high occurrence of parasites {Sabinella) in LFs was probably associated with a low density of parasite predators (, brachyuran crabs associated to urchins) in LF sites. The results suggest three points: (1) A mediated effect due the high specificity of fisheries around the center of the Galap
. Annual report - Western Society of Malacologists. Mollusks; Mollusks. Figure 2. Brachyuran crab prevalence on the urchin spines (E. galapagensis). The HF sites showed significantly greater average values of prevalence of infection compared to the LF sites in the Galapagos archipelago. Discussion The high occurrence of parasites {Sabinella) in LFs was probably associated with a low density of parasite predators (, brachyuran crabs associated to urchins) in LF sites. The results suggest three points: (1) A mediated effect due the high specificity of fisheries around the center of the Galapagos archipelago which causes fishing down marine food webs, that is, the predators of the sea urchins (, lobsters and fish) are fished out, affecting sea urchin densities in HFs (Christensen & Pauly 1998, Pauly et al. 1999), (2) there exists a clear pattern in the distribution and abundance of the parasites and their predator, crabs and (3) in HFs, extraction of lobsters and fish (predators of the sea urchins and crabs, respectively), increase the densities of the sea urchins, but indirectly the occurrence of parasites decreases after the removal of the predators of the crab (, fish). Therefore, the densities of the crabs increase and generate control in the number of parasites. Then, in contrast to the original hypothesis mentioned, a new conceptual model must be proposed to explain the biological interactions between fishing, urchin densities, parasites and snail predators (brachyuran crabs). Prevalencia del parasito Sabinella sharskyi (Gasteropodo: Eulimidae), y daiio subletal en Eucidaris galapagensis (Echinoidea) en las Islas Galapagos, Ecuador El erizo marino mas conspicuo de las Islas Galapagos, Eucidaris galapagensis es parasitado por el gasteropodo Sabinella sharskyi (Eulimidae). Es la linica especie de equinodermo en el Western Society of Malacologists Annual Report Vol. 36, p. 80. Please note that these images are extracted from scanned page images that
Size: 1945px × 1285px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversity, booksubjectmollusks
