Mapping the majestic marine mammals
Published: 15 February 2017
People often think that because marine mammals are an iconic group in the eyes of the public, receiving a lot of media attention, they are well protected. Unfortunately that is not the case. As keystone species in the marine environment, they can not only shape ecosystems but also be particularly vulnerable to perturbations. Marine mammals face a wide variety of human pressures. For centuries they experienced exploitation for food and various products. In the middle of the last century, western society awakened to the damage it was doing to populations of the great whales, and between the 1960s and 1980s moratoria against commercial whaling were brought into effect. However, by then, the pressures upon marine mammals had already shifted with widespread mortality occurring in the world’s oceans as a result of entanglement in fishing gear.
Advances in fishing technology put pressures on fish stocks upon which marine mammals often prey. New pollutants, such as pesticides and PCBs, were introduced into the environment in the 1950s and 1960s, and in particular affected those predators at the top of the food chain, adding to the contamination of inshore areas after the Industrial Revolution. Another important pressure on marine mammals involves noise introduced into the marine environment by shipping, seismic surveys, pile driving, dredging, military sonar and detonations, to name just the major sources.
It has only been as recently as the 1990s that international legislation was introduced to improve the conservation of marine mammals. The cornerstone of nature conservation in Europe is the Habitats Directive (entered into force in 1992), built around two pillars: a strict system for species protection and the Natura 2000 network of protected sites. All cetaceans occurring in Europe are listed in Annex IV of the Directive, requiring strict protection, and two species, the harbour porpoise and bottlenose dolphin, are additionally listed in Annex II, requiring the development of Special Areas of Conservation, where appropriate, as part of the Natura 2000 network. In 2008, the EU Marine Strategy Framework Directive (MSFD) was adopted by the European Union. The MSFD requires Member States to put in place measures to achieve or maintain Good Environmental Status (GES) by 2020, through the development of national marine strategies. Each Member State is required to develop a marine strategy for their waters, in coordination with other countries within the same marine region or subregion. This coordination is to be achieved through the Regional Seas Conventions (HELCOM, OSPAR, Barcelona Convention, Black Sea Convention).
Fundamental to addressing conservation issues facing marine mammals is a good understanding of their distribution and abundance, trends in time and space, and the environmental drivers determining those. This is one of the key topics we are trying to address along with the same for seabirds in the top predator component of MERP. By mapping also human pressures and incorporating metrics for quantifying the impacts of different activities on the full range of species, it should be possible to better inform risk management, and thus support the work of regulators, statutory conservation agencies, industry and other stakeholders.
Keep an eye on the new WP3 projects to see how this work develops.
Dr Peter Evans is the founding Director of the Sea Watch Foundation.