Multi-spectral satellite-airborne management of ice form marine mammals and their habitat in the presence of climate change using a hot spots approach

Abstract

Until the beginning of a world-wide harvest in the 1600s, there was a high abundance of marine mammals in the western Arctic. Especially strong decreases of whales, walruses and phocid species in the Russian Arctic took place during last quarter of the nineteenth and the beginning of the twentieth century (Nansen 1924). Large-scale precautionary measures in the 1960s helped to maintain some diminished populations and preserve them from further declines. Unfortunately, today the population number of virtually all representatives of ice-related mammals is lower than what it was at the first decade of the twentieth century. New population decreases and a worsening of the health status of ice-related marine mammals is reported from many field-based, ship-borne investigations; this situation is directly associated with anthropogenic pressures (Hansen et al. 1996; Ridgway and Harrison 1981, 1989; Zannutdin et al. 2006).