| Popis: |
The Baja California to Bering Sea (B2B) Marine Conservation Initiative seeks to establish a network of Marine Protected Areas within the Exclusive Economic Zones of the NAFTA countries- Canada, Mexico, and the United States. This network is designed to capture ecologically significant habitat for marine species of common conservation con- cern and pelagic regions of high productivity, with due consideration for the inter-annual sea surface temperature fluc- tuations of the El Nino Southern Oscillation (ENSO). Here, we present analytical methods that define pelagic habitat based upon the density of steep temperature gradients, or fronts, and we quantify their spatial and temporal persist- ence over a single ENSO cycle (1996-1999) to benefit marine conservation and marine management strategies. We find that less than 1% of the Northeast Pacific ocean exhibits a persistent ( > 8 mo/yr) concentration of tem- perature fronts (> .2km/km 2 ) within and between years. The Baja California Frontal System (BCFS) is the largest con- centration found within the multinational federal waters, between 0 and 300 km east of Baja California Sur. The BCFS appears more active under La Nina conditions, while the next largest persistent concentration, North Pacific Transition Zone, appears more active under El Nino conditions. We demonstrate habitat functions associated with the BCFS for blue whales (Balaenoptera musculus), swordfish (Xiphias gladius), and striped marlin (Tetrapturus audax). We recommend management and protection for this pelagic "hotspot" to the Mexican government and the tri-national Commission for Environmental Cooperation. |
