WHALES AND SHIP STRIKES: A PROBLEM FOR BOTH WHALES AND VESSELS
Many species of whales and dolphins are vulnerable to collisions with vessels. Most reports of collisions involve large whales but collisions with smaller species also occur. Collisions with large vessels often either go unnoticed or unreported, particularly for the smaller species. Animals can be injured or killed; and vessels can sustain damage. Serious or even fatal injuries to passengers have occurred involving hydrofoil ferries, whalewatching vessels and recreational craft.
The IWC and ship strikes
The IWC is addressing the problems caused by ship strikes through the work of its Conservation and Scientific Committees.
|More details of this work can be found here
The Conservation Committee provides a forum for members of the IWC to report and share information on the measures being taken within their own countries to reduce and record incidences of ship strikes. In addition, the Conservation Committee has established a dedicated Ship Strikes Working Group to develop detailed proposals for mitigation of ship strike events and to co-ordinate work between member governments. This group was founded by the late Commissioner for Belgium, Alexandre de Lichtervelde who died in 2011. Belgium remains committed to this issue and its new Commissioner, Frédéric Chemay, who is also the present Vice-Chair of the Commission, has taken on this role.
In 2010, the IWC’s Ship Strikes Working Group held a joint workshop with scientists and representatives from ACCOBAMS (the Agreement on the Conservation of Cetaceans of the Black Sea, Mediterranean Sea and contiguous Atlantic Area). The workshop reviewed the available information on ship strikes including mitigation measures for reducing ship strikes. The report of the workshop can be downloaded here. It developed a number of important recommendations and these form the basis of the IWC’s workplan to address this important issue. The latest report of the Conservation Committee, which includes its discussions on ship strikes, can be found here.
Quantifying the problem
Every year, the IWC’s Scientific Committee considers methods of estimating the number of whales killed from ship strikes. This is not a simple issue.
|You can read more about this work here
Evidence of ship strikes comes from a range of sources including direct observations from vessels and examination of whale carcasses found floating at sea or washed up on the beach for evidence of collision. In some cases, whales become lodged on the bulbous bows of large vessels and frequently the crew only become aware of this when the ship enters port. However, for every incident that is observed and reported there will be many others that are missed. This makes assessing the conservation implications of ship strikes very difficult.
For some populations, such as the North Atlantic right whale whose main habitat is the busy waters off the east coast of the USA and Canada, the mortality rate is particularly high compared to the overall population size. It is thought that mortality due to ship strikes may make the difference between extinction and survival for this species and mitigation measures have been developed as discussed below. There are also concerns about the high collision rates for the population of fin whales in the Mediterranean. Reported numbers will never give accurate estimates of the numbers of whales involved and so there is a need for estimates based on an understanding of risk and relating this to densities of ships and whales.
There is no universal solution to the problem of ship strikes but clearly the most effective way to reduce collision risk is to keep whales and ships apart. Work on a number of approaches to mitigation is underway but it is essential that measures are carefully evaluated and monitored to ensure that they are working as expected. This work needs to be undertaken in a collaborative way as whales are found within and outside national boundaries. The IWC is working in conjunction with other important bodies such as the International Maritime Organisation (IMO) and further advice to reduce the risk of collision has been produced. You can read this advice here (Also available in Arabic, Chinese, French, Russian and Spanish).
|More information can be found here
Separating whales from vessels is is not as easy as it sounds for both scientific and logistical reasons, but it has been achieved in some areas. In particular, it relies on good information and predictable patterns of whale (and vessel) distribution as well as a practicable alternative route for shipping.
For example, in the Bay of Fundy off the east coast of Canada, long-term data on North Atlantic whale distribution allowed a small adjustment to the shipping lane, adding minimal passage time to shipping, but achieving a substantial reduction in collision risk. A similar approach has been used for shipping lanes approaching the port of Boston on the east coast of the USA. Considerable progress has also been made in Panama and Spain, for example.
Measures to regulate shipping, such as modifying mandatory shipping lanes or establishing areas to be avoided, are decided by the International Maritime Organization. In 2009, the Marine Environment Protection Committee of the IMO accepted a a guidance document on minimizing the risk of ship strikes with cetaceans into its work programme.
What can you do to help?
Ship strikes is an international problem that requires improved knowledge of the behaviour and movements of cetaceans and vessels and a much better understanding of the numbers of collisions and the circumstances surrounding those. The IWC is committed to collecting and collating such information to be able to prioritise areas and species for targeted mitigation measures. A vital component of this is the IWC ship strikes global database.
The global database: a tool for the past, present and future
The IWC has developed a standardized global database of collisions between vessels and whales and an online public data entry system for submitting reports.
|If you have information relating to a collision between any type of vessel and a whale, dolphin or porpoise please click here to enter your information.|
This will open a form that will guide you through the data entry process. Your information will then be passed to the data review group who may wish to ask additional questions.
|To find out more about the database click here
The database includes information on the whales (e.g., species, size, observed injuries) and on the vessels. In many cases there is evidence to suggest a ship strike but often the cause of death cannot be determined conclusively. It is important that the database clearly identifies the level of uncertainty in each case. The objectives of developing the database are to lead to more accurate estimates of the incidence of mortality and injuries, to help detect trends over time, to allow better modelling of risk factors (e.g., vessel type, speed, size), and to identify high risk or unsuspected problem areas.
It is essential that reported data are carefully checked (for example several people may report the same incident) and the uncertainty carefully described. Events reported are therefore carefully checked by the IWC’s data review group.
You can also download a summary table of data entered up until October 2010. These data come mainly from reviews of historical sources including past national progress reports to IWC. Therefore the interpretation as to whether these incidents were indeed definite ship strikes relies on the provider of the data or authors of review papers. None of the data have therefore been subject to the review process currently being established by the IWC data review group. These records include reports of carcasses showing evidence of collisions with vessels as well as direct reports of collisions where the fate of the whale may not be known. For the majority of these records, the available information is limited. These data are provided subject to these caveats and particularly to allow potential data holders to check whether incidents are already in the database.
National and Regional Cetacean Stranding Networks
Many countries have regional or national strandings networks which maintain records of all stranded cetaceans and where possible ensure that sufficient data are collected to ascertain cause of death. In recognition that ship strikes are one of the reasons for cetacean strandings, a revised list of cetacean stranding networks is provided here for information. If you see cetaceans on the beach then you are urged to contact your local strandings network. This global list was last updated in March 2011 and contains additional networks and contact information. Further additions or amendments should be notified to the Secretariat.