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Consultation workbook Bottlenose Whale
Northern bottlenose whale – Scotian Shelf Population
The northern bottlenose whale is a 6-9 m long member of the beaked whale family. A bulbous or melon-like forehead rises abruptly from the short beak in adult females; in young and older males the forehead is less prominent and appears flat. The whale is variable in colour, ranging from blackish in young animals, to light brown in older animals, to yellowish brown or grey (with whitish beaks and heads) in very old males. The small dorsal fin is situated about two-thirds of the length of the body from the nose. Adult females give birth once every two years after a gestation period of one year.
The northern bottlenose whale is found only in the North Atlantic. In the areas where they are found, the water is deeper than 800 metres and they are rarely seen in shallower areas. Although there have been few systematic marine mammal surveys in the offshore waters of Atlantic Canada, there are several known centres of abundance, two of which are found off Canada – the edge of the Scotian Shelf and the Davis Strait. The Scotian Shelf population is described as largely or totally distinct from the Labrador population. For example, the whales of the Scotian Shelf population are approximately 0.7 m shorter than the population seen off northern Labrador. At the edge of the Scotian Shelf, the whales have been seen regularly in three submarine canyons: the Gully, Shortland Canyon, and Haldimand Canyon. These areas are described as the “primary habitat” of the whales with year-round observations. The Scotian Shelf represents the most southerly location where the whales are seen regularly in the North Atlantic.
Bottlenose whales feed primarily on deep-living squid from the genus Gonatus. These squid appear to be the most important component of their diet, but the whales also feed on other animals. Northern bottlenose whales observed in the Gully appear to spend most of their time at great depths foraging for food.
Once whales dive deeper than the reach of sunlight, vision is of little use for navigation. Bottlenose whales have highly developed vocalizing and hearing abilities that permit them to communicate, navigate, and locate prey in canyons and other deep areas.
Northern bottlenose whales are social animals. They are most frequently seen in small groups of up to four whales and occasionally in larger groups of up to twenty whales. They are curious animals who may investigate slow-moving or stationary vessels.
COSEWIC provides the following rationale for designating the Scotian Shelf population of the northern bottlenose whale as endangered:
This population totals about 130 individuals and appears to be currently stable. Oil and gas development in and around the prime habitat of this population poses the greatest threat and will likely reduce the quality of their habitat. However, there is little information as to how this species is, or is not, affected by oil and gas development activities.
Threats to the northern bottlenose whale – Scotian Shelf Population
The Scotian Shelf population of northern bottlenose whales was targeted by whalers in the 1960s. This whaling effort is thought to have led to a decline in the population size.
Current threats to the northern bottlenose whale are poorly understood. However, because of the small size of the population, even activities that may impact only one or two whales each year may pose a threat to the overall health of the population.
There are a variety of potential sources of anthropogenic noise in the marine waters of the Scotian Shelf that produce underwater sounds within the frequency range detectable by northern bottlenose whales. These include commercial shipping, hydrocarbon exploration and development, military activity, underwater detonations, fishing, and research. Based on the global experience with other marine mammals, responses to high levels of anthropogenic noise are mixed and may include habituation, behavioural changes (including displacement), temporary or permanent hearing impairment, and mortality. Evidence of these impacts on marine mammals in the wild is lacking. Other species of beaked whales have experienced harmful effects from loud noise, suggesting that the northern bottlenose whale may be particularly susceptible. The cumulative effects of multiple noise exposure may have long-term population-level effects for marine mammals such as the northern bottlenose whale.
The oil and gas industry uses compressed air guns that emit sound pulses to map areas of subsea hydrocarbon deposits. Research geologists also use airgun technology to study the seabed. The behavioural and physical responses of northern bottlenose whales to airgun sounds are not understood, but seismic surveys are thought to be a threat to this species. For example, surveys could cause the displacement of northern bottlenose whales from preferred habitat. The likelihood and severity of biological effects that might result from being exposed to seismic sounds are thought to vary with the duration and intensity of exposure. In recent years, seismic exploration has occurred near the whale’s “primary habitat”, with the potential for future activities in or near these areas.
Noise is also created by oil and gas exploratory drilling and production activities, with unknown impacts on the northern bottlenose whale.
Sonars have been developed for military, research, and commercial purposes (e.g., fish-finding). Strandings and deaths of several species of beaked whales after the use of military sonars have been reported in other parts of the world in recent years. The precise mechanisms that might cause such strandings are unknown, but it has been suggested that sonars may cause disorientation after which the whales surface too quickly.
Explosives, such as those used in well-severance and other underwater demolition operations, can cause physiological damage to whales and other marine life close to the source. Hearing damage is a concern for whales that use sound to navigate or to find food. Explosions that occur at a distance may change the behaviour of whales.
The propellers of large commercial vessels can produce relatively high levels of underwater sound. This sound may disturb the northern bottlenose whales resulting in displacement or reduced feeding efficiency until the vessel moves away.
Entanglement in Fishing Gear
A small number of northern bottlenose whales have been seen entangled or interacting with fishing gear. In addition, there have been observations of scars and marks on the beaks and backs of this species that are similar to entanglement marks on other whale species. These marks suggest that interactions, particularly with gear that deploy lines, may happen more frequently than has been observed.
Many vessels transit areas occupied by northern bottlenose whales. Ship strikes are a source of injury and death for some species of endangered and threatened whales and may be a threat to this species as well. There are some scars or marks on the whales that may be due to interactions with vessels, but there have been no reported cases of injury or death.
Increased levels of contaminants in areas typically frequented by whales can lead to elevated levels of organo-chlorine and heavy metal contaminants in their body tissues. High levels of contaminants due to industrial development have negatively affected the health of some whale populations in Canada, for example, the beluga whale population in the St. Lawrence River. However, there is no published information specific to contaminants in northern bottlenose whales.
Concerns have been raised about the potential for contaminants from activities such as oil and gas installations and shipping traffic affecting northern bottlenose whales. Ingestion of marine debris, such as plastics, has also been identified as a potential concern.
Protecting the northern bottlenose whale – Scotian Shelf population
The Marine Mammal Regulations (SOR 93-56) of the Fisheries Act govern many aspects of the management of the northern bottlenose whale.
Several additional management measures are already in place to protect this species. In 1994, the Department of Fisheries and Oceans designated a "Whale Sanctuary" in the Gully for the northern bottlenose whale in the Canadian Notices to Mariners, providing guidelines for all marine vessels operating in the area.
In the mid-1990s, the Department of Fisheries and Oceans began consultations and studies to evaluate a marine protected area for the Gully. Interim protection was put in place at that time, including restrictions on petroleum activities in the area. As well, enhanced environmental assessment requirements for activities potentially affecting northern bottlenose whales were put in place to identify and minimize potential impacts.
Some oil and gas operators have instituted their own “Codes of Practice”for the Gully in order to minimize operational impacts on the whales.
In May 2004, the Gully was designated a Marine Protected Area (MPA) under the Oceans Act. The regulations limit the type of activities permitted in the Gully. The MPA provides full ecosystem protection in the central portion of the canyon, an area of known importance to the northern bottlenose whale. No extractive activities are permitted in this portion of the MPA, but research activities may be approved.
Potential Impacts on Stakeholders
Once added to the List of Wildlife Species at Risk, the Scotian Shelf population of the northern bottlenose whale will be protected. If particular activities are assessed to be a threat to the survival and recovery of a listed species, management measures will be put in place to limit those activities and ensure the protection of species at risk.
These measures may lead to a variety of impacts on stakeholders, including additional costs. The following list is not exhaustive, and would be developed further during the recovery planning process in consultation with other government departments and the public. Please use this consultation as an opportunity to comment on omissions.
Aboriginal peoples will be invited to participate in the development of a recovery strategy for the northern bottlenose whale. Management strategies that could affect aboriginal people fishing for commercial species inareas inhabited by northern bottlenose whales may be considered.
If a particular fishing activity is identified to be a threat to the survival and recovery of a listed species, management measures will be taken to address the threat. These measures could include increased observer coverage in certain areas, closed areas, gear modifications, or other measures developed in collaboration with industry that will help prevent and minimize the effects of potential entanglements and interactions.
Oil and Gas Industry
Certain oil and gas activities, such as seismic exploration activity, have been identified as potential threats to the recovery of this species. Such activities will be reviewed and may be restricted in areas defined as critical habitat (if and when identified). The recovery process could identify a range of operational requirements and guidelines for exploration. These guidelines might include time and area exclusions, requirements for marine mammal observers, and other measures deemed appropriate. Proposed oil and gas activities that fall under the Canadian Environmental Assessment Act (CEAA) will need to address the impacts on SARA listed species in accordance with this legislation.
Maritime Forces Atlantic may be asked to prepare guidelines for exercises or underwater site remediation in areas of northern bottlenose whale habitat. They may be asked to refrain from undertaking specific types of exercises in these areas or in areas that could impinge on critical habitat (if and when identified). As identified in SARA, these requirements would be waived in emergencies or if national security were affected.
Those wishing to carry out research on the northern bottlenose whale or in areas of their critical habitat (if and when identified) will be required to comply with strict guidelines. This may limit the types and/or durations of research permitted and may lengthen the preparation time required for planning research projects. All research activity will be subject to a rigorous review process. Research activities in the Gully require additional approvals under the MPA regulations.
The marine transport industry and regulators may be asked to develop guidelines for vessel traffic, similar to those currently in place for the Gully. The industry may be asked to monitor and report on their activities in northern bottlenose whale areas.
Although ecotourism activities in the offshore have been limited to date, there may be future interest in regularly visiting areas frequented by northern bottlenose whales. This activity may require specific guidelines or may be restricted or limited in areas identified as critical habitat.
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