Worldwide dolphin populations are on the decline overall, but ardent conservation efforts have produced a positive trend for several dolphin species that have seen drastic reductions in their numbers. In recent years, international efforts have targeted the actions of several nations, like Japan, that slaughter and trade in dolphin species, and whose cultural activities often trample the wishes of the international community dedicated to conservation. Other countries, such as Peru, serve dolphin on restaurant menus, practices which make coordination and success difficult in international waters. Despite the struggle, these three dolphin species have managed to make a comeback, however currently minute.
The Hector’s dolphin is very susceptible to gill net entrapment off the waters near New Zealand. This small dolphin has benefited from fishing net regulations and is increasing between two and three percent per year since 2006. They must do more because in an average year the nets kill and estimated five to ten percent of the population. In a lifetime of 20 years, a female Hector’s dolphin can only have 4 or 5 calves, so more regulation for gill nets still need to be done to protect this species.
The Vaquita is actually a porpoise, found in the northern end of the Gulf of California in the Sea of Cortez. This 1.5 meter long species is the smallest of all porpoises, and it has been endangered since the 1990’s. The Mexican Government established a bio-marine reserve in 2013 to help preserve the remaining 200 Vaquitas. If the efforts continue, the population may grow to over 250 by 2020, but they will still remain critically endangered for many years to come.
Amazon River Dolphin
The Amazon River dolphin, or boto, declined greatly in the 1990s, but the governments of Venezuela, Peru, Colombia, and Brazil have collaborated to help stop poaching and net entrapment. These river dolphins are also under threat from toxic runoff form irrigated mining operations. Awareness of these illegal gold mining operations is the first step to stopping them. The fishing industry is easier to control, but contamination will be the greatest long term threat to all dolphin species.