Our beaches may seem relatively quiet this winter season, but there's quite a lot of activity further out in deeper water as majestic North Atlantic right whales migrate south along the east coast to feed in warmer waters, and for females to calve and tend their newborns. But for these endangered animals, trouble awaits from entanglement with trawler nets and collisions with commercial fishery and shipping traffic. Fewer than 360 right whales remain, according to the NOAA's fisheries division, including fewer than 70 breeding females.
Right whales are baleen whales, feeding on plankton filtered from the water. They're easily identified by their notched tails and by the white patches known as callosities on their heads. They travel over a thousand miles each year from summer feeding grounds off the Canadian coast to winter grounds off the coasts of North and South Carolina, Georgia and Florida. They're long-lived, with an average life span of 70 years, although centenarians have been reported.
Once plentiful, right whales were hunted to near-extinction by the turn of the twentieth century, prized for the spermaceti filling the cavities of their enormous heads and for the oil held within their 50-foot-long bodies. Because they floated on the surface after being killed, whalers considered them the "right" whales for the ease of harvesting and the bounty each victim provided. As the number of right whales dwindled, other species were hunted until international conventions against commercial slaughter were imposed; and while populations of right whales stabilized, the species has never returned to sustainable levels.
As reported by the Post & Courier, two females - Wolf and Horton - have been sighted off the North and South Carolina coasts as the first arrivals in the annual southern migration. Both females have calved seven times between them, but others haven't been as fortunate navigating some of the world's busiest shipping channels. Mortality remains a threat to the right whales' survival, since the gestation period of a full year and the birth of only one calf means each loss of a mother or calf, or both, keeps the species hovering on the edge. Imposed speed limits in sensitive areas on freighters and commercial fishing boats have been effective, but advocates say stronger federal regulations to monitor and prevent such deaths are needed; and while the NOAA works to develop such regulations, resistance in Congress and from the shipping and fishing industries remains stiff. You can learn more about the NOAA's efforts to preserve these annual visitors to our coasts here.
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