Grouped Species Action Plan

The beaked whales (northern bottlenose, Cuvier`s, Sowerby`s and True`s beaked whales) are species typical of the north Atlantic, but their status and distribution are poorly known.

Northern bottlenose whale Hyperoodon ampullatus . This species is found only in the north Atlantic, this cold-temperate to sub-arctic species occurs mainly in deep water off the continental slope. It is most commonly recorded off western Norway and in the Barents Sea. It also occurs in small numbers around the Northern Isles and Western Isles of Scotland, in the northern North Sea, along the continental shelf break west of Ireland.

Cuvier's beaked whale Ziphius cavirostris . A widely distributed species offshore in all oceans, often found in warmer waters. Rarely recorded north of the British Isles whereas it is the most common beaked whale recorded off the Iberian Peninsula and in the Mediterranean. Most records in UK waters come from the south-west approaches to the English Channel, Western Ireland and the Western Isles of Scotland.

Sowerby`s beaked whale Mesoplodon bidens . This species is only known in cold north Atlantic waters. Recorded mainly in deep offshore waters north and west of the British Isles and Ireland, between Scotland and the Faeroes, and west of Norway, although it occurs at least occasionally south to the English Channel Approaches.

True`s beaked whale Mesoplodon mirus . The distribution is very poorly known, but the few records that exist indicate that it occurs in the Atlantic Ocean west of the Outer Hebrides and Ireland and southwards at least as far as the Canaries.

For most beaked whale species there are too few records to indicate seasonality in UK waters, but northern bottlenose whales are recorded mainly between April and September. No numerical population estimates exist for any of the beaked whale species, but hunting of northern bottlenose whale between the 1880s and 1970s is believed to have resulted in population declines.

The killer whale Orcinus orca is a cosmopolitan species in all marine regions, and is widely distributed in the north Atlantic and in northern European coastal waters particularly around Iceland and western Norway. In the UK, it is most common in northern and western Scotland, rare in the Irish, central and southern North Seas, and English Channel. In UK waters, killer whales occur in all months of the year, but are recorded near shore mainly between May and October. No overall population estimates exist, but recent sightings surveys in the eastern north Atlantic (mainly from Iceland to the Faroes) indicate a population in that region of between 3500 and 12,500 individuals.

The long-finned pilot whale Globicephala melas is found in both hemispheres, in oceanic temperate and sub-polar waters, although may be absent from the north Pacific. It is common and widely distributed in deep north Atlantic waters, but seasonally enters coastal areas such as the Faroes, northern Scotland, western Ireland and the south-west English Channel Approaches; it also occurs south to the Iberian Peninsula and is common in the Mediterranean. Although recorded in UK waters in all months of the year, it occurs in northern Britain mainly between June and September and between November and January further south. Sightings surveys in the eastern north Atlantic in the late 1980s estimate the population at over 700,000 but the difficulties of estimating pod size from survey vessels impose serious limitations to such estimates.

The sperm whale Physeter macrocephalus is found throughout both hemispheres. Widely distributed in small numbers throughout deep waters of the north Atlantic, from Iceland and Norway south to the Iberian Peninsula and east into the Mediterranean. It also occurs along the shelf break north and west of the British Isles and Ireland. In northern European waters, sperm whales are usually either adult or adolescent males which have undergone extensive latitudinal migrations from subtropical and tropical breeding areas. Sightings occur mainly between July and December, and there is evidence suggesting that, increasingly, small groups are remaining at high latitudes into winter months, and mass-strandings may take place. However, the cause of these strandings is unknown. There are no population estimates for sperm whales in the north Atlantic, but past hunting is believed to have depressed population size.

All species of cetaceans are given protection under the Wildlife and Countryside Act 1981 and the Wildlife (Northern Ireland) Order 1985. All cetacean species are listed on Annex IV (Animal and Plant Species of Community Interest in Need of Strict Protection) of the EC Habitats Directive. All whales are listed on Annex A of EU Council Regulation 338/97 and therefore treated by the EU as if they are on CITES Appendix I thus prohibiting their commercial trade. Whaling is illegal in UK waters (Fisheries Act 1981), but neighbouring countries maintain the right to hunt. The UK recognises only the authority of the IWC in matters concerning the regulation of whaling.

An Agreement on the Conservation of Small Cetaceans in the Baltic and North Seas (ASCOBANS), formulated in 1992, has now been signed by seven European countries, including the UK. Under the Agreement, provision is made for protection of specific areas, monitoring, research, information exchange, pollution control and heightening public awareness. Although aimed primarily at dolphins and porpoises, ASCOBANS includes all toothed whales except the sperm whale. The northern bottlenose whale is also listed on Appendix II of the Bonn Convention, as are eastern north Atlantic populations of the killer whale and the North Sea and Baltic Sea populations of the long-finned pilot whale.

The present status of each of the cetacean species considered here is unknown. It is therefore difficult to properly evaluate whether major population changes have taken place. All the whale species considered in this plan spend most of their time offshore where they are likely to be relatively little affected by human disturbance, coastal fisheries and pollution. In general, factors affecting loss or decline are not well understood. However, concerns have been raised about contaminants, traditional drive fisheries, acoustic disturbance and interactions with fisheries.

Contaminants, including organochlorines, may impact the reproductive potential or cause immune suppression in marine mammals, including toothed whales. Demonstrating such effects is extremely difficult, as controlled experiments are generally impossible. Since 1972, oil and gas exploration has used seismic surveys offshore. Seismic survey activity has increased since 1994, and is now used in the Atlantic Frontier - the continental shelf break north and west of the British Isles where many large and medium sized toothed whales occur. Most of the sound energy generated is at frequencies below the main hearing range of toothed whales, but nevertheless there is overlap and potential harm may be caused by direct auditory damage at close distances and interference with navigation, food-finding, and communication further away. Global climate change may also have an effect on toothed whales, although impacts on marine mammals are very difficult to predict.

Although once common in the north Atlantic, drive fisheries now continue only in the Faeroe Islands. Pilot whales may be particularly vulnerable as their social behaviour makes them suitable for herding. Around 22,000 pilot whales were taken in the Faeroe Islands drive fishery between 1970 and 1992.

Killer whales in particular enter nearshore UK waters during the summer, where they may be exposed to a number of human activities that may be detrimental to them, for example disturbance from recreational craft including whale-watching vessels. At present, this is not a serious problem, but such activities are increasing steadily and may pose a threat in the future.

Fisheries, particularly for cephalopods, may affect the abundance or availability of prey species for toothed whales, as may fisheries for other deep-water species. Again, the difficulty in obtaining experimental evidence of such effects means that concerns are at present speculative. There have also been cases of sperm whale, Cuvier`s beaked whale, killer whale, and long-finned pilot whale becoming entangled in fishing gear, but the scale of the problem is unknown. Killer whales in winter commonly associate with the mackerel purse seine fishery north of Shetland. During the 1970s, the mackerel fishery (purse seine and midwater trawls) in the western English Channel was reported to have occasionally caught pilot whales. In the UK, only one Cuvier`s beaked whale and no sperm whales have been recorded as definitely entangled in fishing gear, but both species form by- catches of the Italian swordfish driftnet fishery in the Mediterranean. Pilot whales have been caught in pelagic trawls in the northern North Sea.

The most obvious negative influence upon some large and medium sized toothed whales species has been hunting. The International Whaling Commission imposed an indefinite moratorium on commercial whaling in 1986, by which time the species under consideration here had already been receiving protection. Traditional Faeroese drive fisheries for pilot whales still take place.

Three international north Atlantic Sightings Surveys to estimate abundance were conducted in 1987, 1989 and 1995. The Sea Mammal Research Unit coordinated the international SCANS survey in the North Sea and adjacent waters in 1994. Norway continues to conduct abundance surveys in the eastern north Atlantic. Distribution surveys around the British Isles have been conducted by the JNCC since 1980. The Sea Watch Foundation collects distributional information from a broad range of individuals and organisations. Sightings from seismic survey vessels and hydrophone arrays provide valuable data on the numbers and distribution of cetaceans.

Before licences are awarded by the Department of Trade and Industry (DTI) to offshore blocks for oil and gas exploration, operators are required to conduct a preliminary assessment of impact of their proposed operations. In addition, restrictions on operating practices are included in the conditions attached to each licence to protect areas of sensitivity. Following the award of licences, under the regulations implementing the Environmental Assessment Directive, operators are required to assess the potential impact of their actions. In cases where there is the possibility of significant impact they may be required to undertake a full environmental assessment seeking advice from statutory and non-statutory consultees. If the operation cannot be conducted without causing significant environmental impact, it may not be allowed to proceed.

Guidelines for seismic operators to minimise potential impacts of seismic surveys were agreed with the oil and gas industry, published in 1995 by the then Department of the Environment and subsequently revised in April 1998. Under the guidelines there is a requirement for visual and acoustic surveys of the area prior to seismic testing to determine if cetaceans are in the vicinity, and a slow and progressive build-up of sound to enable animals to move away from the source. Timing conditions may also be imposed on seismic surveys if this will reduce disturbance to known, regularly occurring concentrations of whales.

A JNCC workshop in 1998 on the potential impacts of seismic activities on marine mammals was attended by representatives from the oil and gas industry, geophysical and environmental contractors. They identified information and concerns and discussed possible research needs and regulatory mechanisms.

ASCOBANS has recommended measures in the North and Baltic Seas aimed at protecting dolphins and porpoises, which at the same time would benefit larger toothed whales. Most relevant are the monitoring of fisheries interactions, cetacean health and reduction of by-catches.

Post-mortem and tissues studies of stranded carcasses are carried out to establish body condition and cause of death by the Scottish Agricultural College, and the Institute of Zoology in England and Wales under contract to the Department of the Environment, Transport and the Regions.

Eunice Pinn, Joint Nature Conservation Committee Tel:01224 655718

The following LBAPs are working on Grouped plan for toothed whales:

Originally published in: UK Biodiversity Group Tranche 2 Action Plans - Volume V: Maritime species and habitats (October 1999, Tranche 2, Vol V, p31)