Artículos de revistas
Hydrological connectivity drives longitudinal movement of endangered endemic Chilean darter Percilia irwini (Eigenmann, 1927)
Registro en:
J Fish Biol. 2021;98:33–43
1095-8649
Autor
Vivancos, Aurélien
Górski, Konrad
Manosalva, Aliro
Toledo, Bárbara
Reid, Malcolm
Habit, Evelyn
Resumen
Artículo Movement is a fundamental aspect of fish ecology, and it therefore represents an
important trait to monitor for the management and conservation of fish populations.
This is especially true for small benthic fish, as they often inhabit part of the catchment
where their movement may be restricted by alterations to river connectivity
due to human activity. Still, the movement of these small benthic fish remains poorly
understood, partly because of their small size and their cryptic nature. This applies to
Percilia irwini, an endangered small darter native to the south-central region of Chile.
Its habitat has been affected by the presence of large hydroelectric dams and is currently
threatened by the construction of several others. In this study, the authors
investigated movement patterns of P. irwini from populations inhabiting different
parts of the Biobío catchment, with different levels of connectivity due to natural
and/or human-induced features. The authors combined chronological clustering with
random forest classification to reconstruct lifelong movements from multi-elemental
otolith microchemistry transects. The majority of the movements detected occurred
in an undisturbed part of the catchment. These were directional upstream movements
occurring between capture sites from the lower and the middle reaches of the
river, representing a distance of nearly 30 km, a distance much larger than previously
thought. Nonetheless, in the part of the catchment where connectivity was affected
by human activity, no such movements were identified. This study shows that connectivity
alteration could impede naturally occurring movement and further threaten
the resilience of populations of P. irwini. Furthermore, the results presented are used
to discuss advantages and disadvantages of microchemistry analysis for studying
movement of small benthic fish.