Received: from biology.ucsc.edu (darwin.UCSC.EDU [128.114.141.165]) by enterprise.fuse.net (8.8.5/8.8.5) with ESMTP id XAA18724 for <[log in to unmask]>; Sat, 8 May 1999 23:30:26 -0400 (EDT) Received: from localhost (lonhart@localhost) by biology.ucsc.edu (8.8.8/8.6.11) with SMTP id UAA08635 for <[log in to unmask]>; Sat, 8 May 1999 20:30:17 -0700 (PDT) Date: Sat, 8 May 1999 20:30:17 -0700 (PDT) From: <[log in to unmask]> To: Art Weil <[log in to unmask]> Subject: Re: Question In-Reply-To: <[log in to unmask]> Message-ID: <[log in to unmask]> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Hi Art, Here in California they have quite dramatic effects. For example, both have been implicated with short-term spatial shifts in the distribution of molluscs from the Oregonian and Californian provinces since the Pleistocene. In 1998, I was observing several fish species that are rarely seen north of Pt. Conception (the major biogeographic barrier that separates the above-mentioned regions). Along with adult and juvenile fishes, plankton tows netted lobster and mantis shrimp, neither of which naturally occur in central California. Certainly veligers were making their way northward. We won't see the impact until juveniles get large enough, but certainly previous ENSO events have carried subtropical and warm-temperate molluscs northward. I am in the middle of co-authoring a manuscript on several range extensions in California, and ENSO events are a likely mechanism of transport. The mounting evidence of increasing sea surface temperatures this last century also contributes to the northward shift of warmer water species. Also, ENSO events impact the coastline to depths of 100 m (really warm water), so subtidal species are definitely impacted. Do La Ninas bring more cold-water species south? I think we'll be able to detect that in a year or two. Cheers, Steve > What effect does the El Nino and La Nina shifts in water temperature > have on mollusks? I don't imagine there is much change deep down, but > what of species dwelling only slightly below tide lines? Steve Lonhart Department of Biology Office: (831) 459-4026 University of California FAX: (831) 459-4882 Santa Cruz, CA 95064 email: [log in to unmask] WEBSITE: http://www-biology.ucsc.edu/people/potts/lonhart/