My co-author and I are pleased to inform you about this recently published 
article in Frontiers on Marine Science.

Abstract
A long-term study of a common bottlenose dolphin (Tursiops truncatus) population
inhabiting the Gulf of Guayaquil, Ecuador (2330 S, 79200W), has been carried out
for almost 30 years. Similarly, as in other parts of the world, this population 
is structured
socially and spatially in well-defined subunits or communities. Two of these 
communities,
referred to as Posorja and El Morro, have been studied with major intensity in 
the
last 10 years in the western inner estuary, among others to calculate population
parameters that allow assessing their viability in time. Calculated parameters 
include
annual abundance, age and sex composition, annual crude birth rate, calf 
survival, calf
production interval, and average annual mortality/emigration.With these 
parameters and
others derived from other better-studied populations, the trend of both 
subunits was
modeled using the software Vortex. Results show that even under an optimistic 
scenery
both communities will be extinct in the short (Posorja) and mid-term (El 
Morro), if current
stressors continue. Most population parameters calculated in both communities 
show
similar values as in populations elsewhere, but a very low calf survival in 
Posorja and
high mortality/emigration ratios in adults, and probably in juveniles in both 
communities,
contribute to this trend. Population deterioration seems to be the result of 
different
human-induced threats such as fisheries, maritime traffic and others still not 
well
assessed, as well as stochastic demographic events. We recommend taking actions
in the short term to halt population decline addressing the major causes of 
mortality
affecting these dolphin communities.

The article is free available from the editorial site DOI: 
10.3389/fmars.2020.537010.

Regards
Fernando Félix

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