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Research FEMM is the pioneer institution doing scientific research on marine mammals in Ecuador . A summary of the main studies carried out and the most relevant results are presented below. Details of these studies can be found in the section publications .
The main scientific activities carried out by the FEMM include:
Socio-ecological study of the coastal bottlenose dolphin Tursiops truncatus in the Gulf of Guayaquil (1990-1992) . Between February 1990 and October 1992 a study on the ecology and social organization of the costal bottlenose dolphin ( Tursiops truncatus ) in the interior estuary of the Gulf of Guayaquil was conducted. Weekly trips were made in a 5 m long boat with an outboard motor between Guayaquil and Puná Island on the Guayas River outlet. Also different secondary routes were taken across the inlet of the Estero Salado and the canals that separate the different islands of the estuary. Navigation time accounted for 1,112 hours, including 260 hours with the animals. A total of 4,021-4,351 dolphins in 241 groups were recorded. Photographs of their dorsal fin were taken for photo-identification. One of the results obtained from this study was the determination that the groups of bottlenose dolphins turned out to be considerably bigger during the dry and cold season (June-November) (P<0.01) and considerably more abundant (P<0.05). The population under study was estimated in 637 individuals ( I.C. 95% 541-733). This population is organized in communities of about 120 individuals with well defined home ranges, although with overlap in their boundaries. 441 dolphins were identified and their association pattern established. Within the communities the groups were organized in bands, which showed a preference for specific sites of the community's home range. The social organization of this population is similar to what found in other sites, but with some differences. For example, there is no reproductive seasonality and only one pair of dominant males are present in each community, whereas in other sites several pairs of adult males have been found in the same community. This study also provides information about distribution, use of habitat, behavior, feeding habits, among others. Study on population dynamics, social organization and behavior of humpback whales (Megaptera novaeangliae) on the Ecuadorian coast (Puerto López, Puerto Cayo, Salinas ) (1991-2004) . The humpback whale research in Ecuador started in 1991 around La Plata Island , in the province of Manabí . Later it was extended to Puerto Cayo and Salinas . This study helps to set up whalewatching programs in Ecuador . Since 1994, FEMM volunteers have been using tourist vessels to study the behavior, use of habitat, social structure and tourism impact on the humpback whales. One of the techniques commonly used with humpback whales here and elsewhere is photo-identification. The coloration patterns on the ventral side of the tail enable us to identify each whale individually. Up to now our catalogue is made up by some 700 different whales. Photo-identification has allowed us to learn about some aspects related to habitat use and movements between localities in Ecuadorian waters and in other parts of the Southeast Pacific. Generally speaking, humpback whales in Ecuador show a low fidelity to the study area. This is deduced from the low number of animals resighted within the same reproduction season. Also there are reports about humpback whales identified by the FEMM that were seen in Colombia, south of Chile and at least 32 of them to the west of the Antarctic Peninsula , where their feeding grounds are located. The inter-annual resighting rates have allowed us to estimate the size of the population in 1997 in 1,922 individuals (I.C. 95% 77-3,367). In 2003 another estimation showed that the whales had increased their number to 2,470 (I.C. 95% 88-4,852), a net increase of 29,5% in seven years, with an average annual growing rate of 4%. Studies by FEMM have shown that the whales distribute in shallow waters of less than 60 m during their stay in Ecuadorian waters. Only 2.5% of the sightings were made in waters of over 60 m deep, with a maximum of 104 m . Mothers nurse their offsprings in shallow waters until migration to the Antarctic that starts by October. Study of small cetaceans bycatch in artisanal fisheries ( Santa Rosa and Puerto López) Between December 1992 and December 1993, a study was carried out to establish the level of bycatch of small cetaceans in artisanal fishing gear in two important ports of the country: Puerto López and Santa Rosa . During the study, a fleet of 6 boats that used gillnets were monitored. At arriving from the sea, the crew members were interviewed to determine the number of dead dolphins, species and the site where the interaction occurred. Observers where onboard in 64 trips (2.3%). The fleet from Santa Rosa made 1,699 trips in that from Puerto López 1,065. The mortality rate in the Santa Rosa fleet varied between 0.075 and 0.127 dolphins per trip (average: 0.104). The species involved included the common dolphin ( Delphinus delphis ) (90%), the short-finned pilot whale ( Globicephala sp ), the spotted dolphin ( Stenella attenuata 0.6%), the dwarf sperm whale ( Kogia simus ) (1.1%) and other no identified species (1%). The largest bycatch took place between March and August. The mortality rates in the Puerto López fleet were considerably lower: between 0.011 and 0.066 dolphins per trip (average: 0.038). The species involved were the same as in the case of Santa Rosa , but the proportions were different, i.e. common dolphin (67.5%), short-finned pilot whale (17.5%), spotted dolphin (10%) and no identified species (5%). The largest bycatch took place between May and September. The fleet with observers aboard reported a similar mortality rate for Puerto López (0.034 dolphins per trip), but the rate in Santa Rosa turned out to be three times higher (0.286). The fleets caught 217 dolphins during the study period. Based on these rates we estimated that in that year the complete fleet of Santa Rosa captured 1,150 dolphins (I.C. 95% 874-1,426) and that of Puerto López 156 (I.C. 95% 99-213). In spite of this high rate of bycatch, local authorities have not taken any measures to mitigate the impact of the artisanal fishing on small cetaceans populations. Marine mammal strandings Marine mammal strandings have been an important source of information to learn about the species that frequent Ecuadorian waters. FEMM maintains records of these events since 1987. The search efforts have not been systematic but rather casual, although during 1993 and 1995 we organized 6 monitorings in the province of Guayas to record marine mammals beached. In 1998, a report was published with 94 cases occurred between 1987 and 1995, including the first record of a mass stranding on the mainland coast of Ecuador : 56 false killer whales ( Pseudorca crassidens ). The report also included two species that were reported in Ecuadorian coastal waters for the first time, the stripped dolphin ( Stenella coeruleoalba ) and the short-finned pilot whale ( Globicephala macrorhynchus ). Other 12 species of cetaceans and one pinniped were also recorded. The Odontocetes included: coastal bottlenose dolphin (n=30), sperm whale (n=25), spotted dolphin (n=7), stripped dolphin (n=2), false killer whale (n=2), Cuvier's beaked whale ( Ziphius cavirostris ) (n=2), short-finned pilot whale (n=1), short-beaked common dolphin ( Delphinus delphis ) (n=3), Risso's dolphin ( Grampus griseus ) (n=1), Pygmy killer whale ( Feresa attenuata ) (n=1). The Mysticetes included: the Bryde's whale ( Balaenoptera edeni ) (n=2) and the humpback whale (n=4). The pinniped was the South American sea lion ( Otaria flavescens ) (n=11). Study of a South American sea lion (Otaria flavescens) colony at Punta Brava, Salinas (2002) In spite of the fact that no reproductive colonies of pinnipeds exist on mainland Ecuador , three species have been recorded: the Galapagos sea lion ( Zalophus wollebaeki ), the South American sea lion ( Otaria flavescens ) and the Galapagos fur seal ( Arctocephalus galapagoensis ). From the three species, only the South American sea lion is found throughout the year. A small colony of this species locates in Punta Brava, Salinas , at least since the El Niño phenomenon 1997-1998. The number of animals varies during the year from 2- 3 in warm months (January-March) until over 30 in cold months (September-October). This is the northernmost colony of this species along its distribution range, which includes both coasts of South America . As the site is of easy access, the sea lion colony at Salinas offers a great opportunity to study the behavior and ecological aspects of this species.
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