Spearfishers in Chile

In theory, the evolution of scuba gear and wetsuits in spearfishing allow divers to produce a more abundant catch. However, Natalio Godoy from the Pontificia Universidad Católica de Chile and colleagues found that the spearfishers’ catches are becoming less diverse and abundant in the temperate reefs in northern and central Chile. The result, as they suggest in a recent study published in Ecological Applications, is likely due in part to the spearfishing activities themselves.

Godoy and colleagues used several methods to obtain information on the state of reef fish communities in Chile since records of spearfishing activities, and landing records specific to certain regions, are not required by the government. Therefore, the researchers examined data from nation-wide official landing records, the catch from the top 20 divers in the 1971 and 2004 world spearfishing championships and the perceptions of local spearfishers.

They found that the average mass of reef fish captured decreased, the percentage of discarded fish decreased and the total number of species caught decreased drastically in the 30 year span between championships. The interviews, on the other hand, contributed an even greater understanding of the status of the fisheries: Divers reported that they were catching, and local markets were accepting, species of fish that were not consumed just 10-15 years ago.

Jason Tylianakis

Loss of canopy cover in rainforests—compared to the other fragmented habitats in Manabi in southwest Ecuador—leads to a region-wide loss of diversity in species interactions, said researchers from the University of Canterbury in New Zealand. As Jason Tilianakis and Etienne Laliberté reported in the June issue of Ecology, the food webs and interactions between parasitoids and their bee and wasp hosts were simplified and homogenized across habitats. As it turns out, land use was not the major contributor to this loss of interaction diversity: The researchers proposed that the lack of canopy cover in the managed and abandoned coffee agroforests and pasture and rice fields allowed for easier access as parasitoids searched for their bee and wasp hosts. In this edition of Field Talk, Jason Tylianakis discusses his findings, the fragmented habitats of Ecuador and the Homogecene era.

Ecology 2009 90:1, 208-217