Photo-Identification Methods Reveal Seasonal and Long-Term Site-Fidelity of Risso’s Dolphins (<i>Grampus griseus</i>) in Shallow Waters (Cardigan Bay, Wales)

A photo-identification study on Risso’s dolphins was carried out off BardseyIslandinWales(July to September, 1997-2007). Their local abundance was estimated using two different analytical techniques: (1) mark-recapture of well-marked dolphins using a ‘closed-population’ model;and (2) a census technique based on the total number of identified individual dolphins sighted over the study period. The mark-recapture estimates of 121 (left sides;64 - 178 95% CI;CV 0.24) and 145 dolphins (right sides;78 - 213 95% CI;CV 0.24) closely matched the census technique estimates (population size of 90 - 151). It was found that the dolphins showed a degree of long-term and seasonal site-fidelity. A first long-distance match was made for Risso’s dolphins (319 km) betweenBardseyIslandandCornwall, confirming they can be wide-ranging animals. This study demonstrates that the combination of systematic and opportunistic photo-ID studies has complementary value as a population assessment tool in generating the first local abundance estimate for Risso’s dolphins inUKwaters. From the conservation perspective, these studies confirm the regular presence of Risso’s dolphins in these waters and the presence of calves shows breeding.BardseyIslandmay be part of a network of localities that are important habitats to this species where it may take advantage of prey abundance in shallow waters. As such, results of this study may provide assistance to include the Risso’s dolphin in future regional conservation strategies including the envisaged marine protected areas.

Myth and Momentum: A Critique of Environmental Impact Assessments

Environmental Impact Assessments (EIAs) are designed to evaluate all reasonably foreseeable environmental consequences of human activities. Appropriate governmental scientists traditionally produced EIAs for management agencies in many countries. However, many EIAs are now contracted out, often to the lowest bidder without due consideration of expertise. Others suffer from limited agency resources. Consequently, many EIAs have become insufficiently researched documents that draw heavily from previous EIAs while being rushed to completion to meet legislative deadlines or avoid delaying projects. Habitual treatment of topics often ignores recent scientific literature, perpetuating previous misconceptions and analytical flaws. Common problems in EIAs discussing wildlife include: a focus on lethal takes, with little consideration of non-lethal impacts or habitat degradation;a general dismissal of the possibility that non-significant (to the resource) impacts can, when combined, become significant;and the assumption that behavioral habituation in animals represents an end of impact. Incentive to break the cycle is somewhat lacking in this now often commercially competitive environment, where contracts are increasingly awarded by industry, generating potential conflict of interest. We believe investment in thorough, impartially written, scientifically-based and up-to-date EIAs is important for appropriately representing and managing ecosystems and their resources and avoiding potentially expensive litigation.