PosterPDF Available

Preliminary results of cetacean diversity off the Pacific Ocean of Nicaragua (Central America)



This is the first study that has been conducted in the waters of Nicaragua (Central America) along the Pacific Ocean to assess the diversity and occurrence of cetaceans. Boat based surveys were carried out in San Juan del Sur (South-Western Nicaragua) and in Padre Ramos (North-Western Nicaragua) in August 2015 and January -March 2016. Boat based surveys were also effectuated in San Juan del Sur in July 2016 as well as Land based surveys from January-March 2016 (93h of effort). During this period 166 hours and 189 hours of boat based effort has been spent in San Juan del Sur and Padre Ramos respectively. 104 Sightings were recorded during the surveys and 6 cetacean species were identified: one mysticete (Megaptera novaeangliae (n=13)) and five odontocetes (Stenella attenuata (n=70), Stenella longirostris (n=1), Tursiops truncatus (n=17), Steno bredanensis (n=1), Pseudorca crassidens (n=2)). For each sighting: species, groups size, geographic position and primary behavior was recorded. These results will have important implications for future spatial management in the frame of the construction of the canal of Nicaragua.
Joëlle De Weerdt1, Victoria Pouey-Santalou1, Etienne Pouplard1
1 ELI-Scientific, Allée de Verdalle 39, 33470 Gujan-Mestras, France.
Preliminary results of cetacean diversity off the Pacific
Ocean of Nicaragua (Central America)
We would like to thank our foundations and research groups for their support and guidance:
Joëlle De Weerdt
First systematic study conducted on
cetacean research along the Pacific Ocean
of Nicaragua (Central America)
No scientific data available on cetacean
diversity in the country
Assess the presence and occurrence of
cetaceans in Nicaragua
Boat based survey effort
2015-2016 (Fig 2 & 3)
PR : 189h -SJDS : 166h
2015-2016 PR
attenuata X X
bredanensis X
crassidens X
longirostris X
truncatus X X
novaeangliae X X
Boat based surveys on a 7m fiberglass boat, sea state <4
on Beaufort scale in San Juan del Sur SJDS (South-
Western Nicaragua) & in Padre Ramos PR (North-
Western Nicaragua) (Fig 1.)
Survey period : August 2015 / January -March 2016
(SJDS & PR) and July 2016 (SJDS only).
For each sighting: species, group size, geographic
position and primary behavioral activity were assessed
Encounter rate= N/L With N= Number of encounters &
L = Distance surveyed (Nm)
Padre Ramos San Juan del Sur
6 different species of cetaceans has been observed along the Pacific coast of Nicaragua during 2015-2016.
Encounter rates are higher for humpback whales and pantropical spotted dolphins in San Juan del Sur. Mean group sizes are in the
same range for most of the species encountered on both study sites.
More investigation is needed to unravel seasonal variations in the occurrence of the different cetacean species.
Fig. 1: Localization of the study sites in Nicaragua
# of
% sightings
Mean group
# of
% sightings
Mean group
Megaptera novaeangliae 6 14.6 2.3 0.4 8 12.5 1.5 1.1
Steno bredanensis 1 2.4 4.0 0.1
Stenella attenuata 23 56.1 7.9 2.0 47 73.4 7.6 6.2
Tursiops truncatus 9 22.0 3.7 0.8 8 12.5 3.5 0.8
Stenella longirostris 1 1.6 2.0 0.1
Pseudorca crassidens 2 4.9 7.0 0.1
Total 41 100 64 100
Padre Ramos
Fig. 2: Effort and distribution of the different cetacean species in Padre Ramos Fig. 3: Effort and distribution of the different cetacean species in San Juan del Sur
The distribution patterns of
the different cetacean species
differ between the two study
5 species observed in PR
and 4 species observed in
Table 1 : % sightings, Mean group size and encounter rate of each
cetacean species occurring in PR and SJDS.
Mean group sizes:
Similar for all the dolphin species occurring on both study sites
Slightly higher mean group size for humpback whales in SJDS
compared to PR
Encounter rates:
Similar for T. truncatus between the two study sites
Higher for M. novaeangliae and S. attenuata
... This species is listed as "Least Concern" on the IUCN Red List (Kiszka & Braulik 2018). Spinner dolphins and pantropical spotted dolphins were reported in the ETP and in Central American waters through sighting and stranding data (Cabrera et al. 2014, De Weerdt et al. 2017Oliveira et al. 2011;Perrin & Gilpatrick 1994;Rodriguez & Cubero 2001). ...
Full-text available
Documenting marine mammal strandings provides important information needed to understand the occurrence and distribution patterns of species. Here, we report on strandings of cetaceans on the Pacific ( n = 11) and Caribbean ( n = 2) coasts of Nicaragua, documented opportunistically from 2014 to 2021. Strandings included three species of baleen whale (blue whale Balaenoptera musculus , Bryde’s whale Balaenoptera edeni , humpback whale Megaptera novaeangliae ) and five species of toothed whale (dwarf sperm whale Kogia sima , Guiana dolphin Sotalia guianensis , pantropical spotted dolphin Stenella attenuata , spinner dolphin Stenella longirostris , Cuvier’s beaked whale Ziphius cavirostris ). These are the first published accounts of blue whales, Bryde’s whales, dwarf sperm whales, and Cuvier’s beaked whales in Nicaraguan waters. Limited resources and the advanced decomposition of animals prevented necropsies in most cases, the identification of the causes of mortality in all cases, and the species identification of two dolphins. Information derived from these stranding events offers new insights into the occurrence of marine mammals on the Pacific and Caribbean coasts of Nicaragua and Central America.
ResearchGate has not been able to resolve any references for this publication.