Articles:
Páez-Rosas, D., Riofrío-Lazo, M., Ortega, J., Morales J.de D.,,
Carvajal, R., Alava, J.J. 2018. Southern elephant seal vagrants in
Ecuador: a symptom of La Niña events? Marine Biodiversity Records 11:
13. https://doi.org/10.1186/s41200-018-0149-y
Abstract
Background
Extralimital observations of pinnipeds are important to
understand the effects of changing climates on our oceans and the distribution
of these species. The southern elephant seal (Mirounga leonina) is a
known vagrant species that moves over long distances. We report three new
records of M. leonina in interior freshwater tributaries of the Guayas
River Estuary Basin (Gulf of Guayaquil) and northern coast of Ecuador between
October 2017 and January 2018 during a cold episode of La Nina event in the
southeastern Pacific.
Results
The elephant seals were identified according to their large
size (~ 5 m for adult and 2–3 m for juveniles/subadults), the head to
neck size ratio, and the size and external morphology of the proboscis, which
was used as a key trait to differentiate M. leonina from the Northern
elephant seal (M. angustirostris). The observations of M. leonina
in Ecuador highlight an extreme movement covering an assumed total distance of
approximately 8000 km from the circumpolar region. The cold event “La
Niña” with sea surface temperature anomalies ranging − 1.5 °C to
− 0.5 °C in October 2017 likely triggered the extralimital movements of
these animals.
Conclusion
Recurring observations of M. leonina in the Guayaquil
Gulf suggest the importance of this highly productive region and tropical
estuarine-riverine habitats as temporary haulout sites for resting. These new
findings indicate that vagrant individuals influenced by oceanographic events
and eco-physiological processes are reaching this region more frequently than
previously thought.
Date of publication: Published online on June 20, 2018
Links:
https://rdcu.be/1dnP
https://link.springer.com/article/10.1186/s41200-018-0149-y
Jiménez, P.J., Alava, J.J., Castro, C., Samaniego, J. and Fair, P. 2018.
Stranding of Small Cetaceans with Missing Fins Raises Concerns on
Cetacean Conservation in Ecuador: Bycatch or Targeted Fisheries?.
International Journal of Fisheries Science and Research 2(1): 1006.
Abstract
Among anthropogenic threats to
marine mammals, bycatch is one of the major and increasing concerns.
This
report describes three species of small cetaceans, including a
short-beaked common dolphin (Delphinus
delphis), a bottlenose dolphin (Tursiops truncatus), and two dwarf sperm
whales (Kogia sima), which were found stranded with pectoral fins,
dorsal fins and caudal fin removed. The dolphins were found at the
beaches of San José de Las Nuñez and San Pablo, respectively (Santa
Elena Peninsula Province on 14 August 2017), while the dwarf sperm
whales were found in Puerto Lopéz and Crucita (Manabí Province) in July
2014 and August 2015, respectively. Possible explanation for the
dolphins and dwarf sperm whales missing fins support the event as a
possible case of fishery interaction or bycatch with systematic removal
of their fins. Although remnants of artisanal gillnets were not found
near the two dolphin species, one of the dwarf sperm whales showed marks
of artisanal gillnets on the body as evidence of bycatch. Trade of
dolphin carcasses and their parts for bait by fishers cannot be ruled
out as there is some evidence of this practice in the past. Both
dolphins species are vulnerable species at the national level and
commonly involved in incidental captures with gillnets of artisanal
fisheries in Coastal Ecuador. Cetacean bycatch is a grave conservation
problem affecting several cetacean species in Ecuador’s waters.
Fisheries and environmental authorities must be vigilant and enforce
actions to proactively mitigate possible anthropogenic impacts and
promote environmental education activities in fishing communities to
conserve vulnerable dolphin species in Ecuador’s waters. Further, to
comply with new rules and regulations of the US Marine Mammal Protection
Act (MMPA) intended to reduce the bycatch of marine mammals in foreign
commercial fishing operations that export fish and fish products to the
United States, a regulatory program is urgently needed to mitigate and
reduce fisheries interactions with marine mammals in Ecuador.
Date of publication: Published on May 1, 2018
Link: http://smjournals.com/fisheries-science-research/in-press.php Juan Jose Alava, PhD
Adjunct Professor
Resource and Environmental Management, Faculty of Environment,
Simon Fraser University
8888 University Drive,
Burnaby, British Columbia V5A 1S6,Canada
E-mail: jalavasa@sfu.ca
Research Associate, Nippon Foundation- Nereus Program
Institute for the Oceans and Fisheries
Faculty of Science, The University of British Columbia
AERL 313.02-2202 Main Mall | Vancouver, BC V6T 1Z4 Canada
http://oceans.ubc.ca/juan-jose-alava/
https://www.researchgate.net/profile/Juan_Jose_Alava/contributions?ev=prf_act
https://scholar.google.com/citations?user=J_hAHnwAAAAJ&hl=en