by Manuel Arechavaleta and Roberto Montero, Canary Cetacean Institute

Almost a third of the 78 cetacean species existing in the world have been recorded, through strandings or reliable sightings, in the Canary Islands territorial waters. The development of new acoustic techniques has enabled recent surveys to record and predict that sperm whales, Physeter macrocephalus, might actually constitute the most common cetacean species in the Canaries. However, present whale-watching activities are mainly centred around the resident populations of short-finned pilot whale, Globicephala macrorhynchus, and bottlenose dolphins, Tursiops truncatus, found in the deep waters close to the west and southwest coasts of Tenerife.

In 1992 the public company of tourism promotion, nature and leisure (SATURNO) started a project looking into the impacts on pilot whale behaviour caused by recreational boat trips and how these might be mitigated against. As a result of their recommendations, the Canary Cetacean Institute was founded in January 1995 by the Counsel of Tourism and Transport of the Canary Government and managed by SATURNO. It is located in Playa de las Americas, Tenerife, with the aim of researching and conserving cetaceans as well as promoting a responsible local whale-watching industry.

Up until the late 80s only a few whale watching trips took place and pressure from their activities was minimal. In 1991 the Cousteau Foundation visited the islands to make a documentary film. Once widely shown, this directly or indirectly, caused a marked increase in the flow of visitors and the number of companies operating in this sector. There are currently between 35 and 50 different types of vessels offering whale orientated trips from ports and harbours along the west coast of Tenerife. These operate throughout the year and each vessel does several trips a day.

In 1992, 125,000 whale watchers were involved and by 1994 this had risen to around 250,000. The Institute now put the figure at more than 700,000 which makes the Canary Islands one of the leading countries in the world for this activity. It has become a very profitable business worth more than US $13 million to which other indirect benefits (souvenirs, taxis, coaches, food and drink suppliers, etc) should be added. Since the cetacean populations are found close to coastal tourism resorts it is possible for one in six of the 4 million annual visitors to take part in this activity.

As the trips are principally concentrated on only one species, and worse still, only one population in a reduced area, it is not surprising there are actual and potential saturation problems arising. The social groups sighted are generally the same throughout each day and you can often see several vessels around one group. This is because skippers direct themselves to other vessels already surrounding whales in order to save time.

In November 1995 the Canary Government published a law to regulate whale watching activities. A Code of Conduct was imposed which obliges operators to apply for authorization and have onboard a guide knowledgable about cetaceans. A watch system was introduced whereby a boat patrols the area daily to report on any infringements. The Canaries are a pioneer in this respect being the only European country having a law and watch system specifically in place for whale watching.

Besides giving informative talks in local high schools and at other public venues the Institute will shortly be launching a much wider conservation campaign through the media. The best way to control Code of Conduct violations is by encouraging tourists to collaborate with the authorities by not embarking on vessels unless they have a permit; by reporting skippers whose actions might be deemed detrimental towards the whales; and by demanding more constructive information. The granting of a blue flag concession or being offered some other form of “quality” service distinction is under consideration so that tourists can choose operators who treat cetaceans with the respect they are entitled.

Scientific Programme

The Institute’s main research focus is on the social ecology of short-finned pilot whales which have only been observed in an exclusive 200km2 area along the 1000m depth contour off southwest Tenerife. Through photo-identification techniques whales are individually recognized using the natural nicks and scars seen on their dorsal fin or any other part of the body easily visible on the surface. In this way a population catalogue is obtained which has different information on each animal (age, sex, sightings and positions, etc). After storing this information on a database analysis can then be carried out on population dynamics, structure and composition of social groups, inter and intra group relations, distribution, faith as to groups and area.

Initial cluster analysis identified 46 pods, averaging 12.2 ± 1.3 whales (mean ± SE), with an average age/sex composition of 2.5 ± 0.2 males, 2.2 ± 0.4 mothers, 4.7 ± 0.5 unknowns and 3.0 ± 0.5 immatures. Associations between pods were significantly higher during the summer months of April-September, corresponding to the peak occurrence of newborns, and (using a 12-month gestation) the peak conception period. This provided support for the genetic finding that males are not the fathers of the calves in their own pods by suggesting that mating could occur when pods travel together. Comparisons of age/sex class associations showed that within pods, the highest ranked associations of mothers were with other mothers, in contrast to when two different pods travelled together and the mothers highest associations were with adult males. If breeding was occurring within pods, higher associations would be expected between reproductive females (i.e. mothers) and the males. If breeding does not occur between members of the same pod, but only when pods meet, then the strong cohesive nature of pilot whale society must be based on feeding requirements. It may be that the hunting and capture of squid requires a high degree of cooperation best cultivated in closely related kin groups.

The population catalogue was initiated by Dr James Heimlich-Boran in 1991 through a research project funded by Cambridge University, U.K. The Institute, in collaboration with this researcher, has continued to update this catalogue and more than 700 animals have now been identified, from which just over half are considered as resident in the area.

A spatial distribution map of the pilot whale population has been created using 1 mile squares classified into high, medium and low use areas. This map has also been analyzed with environmental parametres such as depth, submarine topography, resources, currents, distance from the coast, and sea surface temperature. This information was derived from NOAA-14 satellite imagery and studied in collaboration with the Department of Physics of La Laguna University.

One of the Institute’s priority lines of research is to measure and analyze the impact caused by tourist boats on the pilot whale population. This activity is difficult to estimate but results to date show that as a consequence of vessels being present, momentary changes in respiratory patterns are produced (which are regular under normal conditions), a dispersion of the social groups comes about and behavioural habits change. The next step is to measure and characterise these impacts as to type and number of vessels, their manouvres and distance from the whales. Such information is vital for future management and will determine the real loading capacity of the tourism activity from the point of view of pilot whale tolerance.

To determine this loading capacity we must estimate the number of pods sighted daily in the area (and their seasonal variation) and establish the maximum number of permits being issued by the Canary Government. This is to ensure that no more than three vessels gather around any one pod at a time. If the pods “available” are less than the number of tourist vessels operating then it will become necessary to limit watch time. If there are seasonal variations then the need to vary the number of permits issued will also have to be considered.