Caracterización de la población de Diadema antillarum Philippi en el Oeste de Cayo Santa María
Fecha
2019-06
Autores
Rodríguez Hernández, Elena
Título de la revista
ISSN de la revista
Título del volumen
Editor
Universidad Central "Marta Abreu " de Las Villas
Resumen
En 1983 y 1984, las poblaciones de
Diadema antillarum
sufrieron una mortalidad masiva en
todo el Caribe; la cual redujo las densidades de entre
93 y 98%. Este evento indujo cambios
en la estructura y funcionamiento de las comunidades coralinas; provocando un cambio de
fase, de arrecifes dominado por corales pétreos a arrecifes dominados por macroalgas. En
Cuba sólo hay un registro sobre el estado
de sus poblaciones antes del evento de mortalidad
y los estudios recientes se concentran en el occidente del país. Este estudio caracteriza la
población de la especie al Oeste de cayo Santa María. Para esto se realizaron un total de
103 transectos de 20 m
2
durante tres muestreos, entre junio de 2016 y junio de 2018. Se
obtuvo un total de 432 registros de
D. antillarum,
de los cuales
el 97,16% se encontraba
protegido y el 2,84% expuesto. La densidad media sufrió una disminución durante los tres
años, provoca
do por una disminución significativa de la densidad de individuos adultos. Esto
se reflejó en una disminución del tamaño y la cantidad de grupos. Por lo que, durante el año
2016 el patrón de distribución espacial fue fuertemente agregado y este cambió haci
a un
patrón regular. La estructura etaria de la población también cambió a partir de disminución
de la densidad, de un predominio de individuos adultos a un predominio de juveniles.
Además, se ratifica a
D. antillarum
como el herbívoro principal, dado que
cuando la densidad
del erizo fue mayor a 0,5 ind/m
2
la cobertura de macroalgas no superaba el 40%.
In 1983 and 1984, a massive mortality of Diadema antillarum populations occurred i n the Caribbean; the densities were depleted at 93 and 98 %. This event induced changes in the structure and functioning of the coral reefs communities; by causing a phase shift, from reefs dominated by stony coral to macroalgae dominated. In Cuba there is only a report of population status before the event and recent studies are concentrated in the western half of the country. This study characterizes the population of the species westwards of Santa María key. For this, a total of 103 transects were carrie d out, of 20 m 2 each, during three years, between June 2016 and June 2018. A total of 432 records of D. antillarum were obtain, of which 97.16% found protected and 2.84% exposed. The population density suffered a decrease during the three years, caused by significant reduction of the density of adult individuals. This it was reflected in a decrease of the size and the quantity of groups. During the year 2016 the pattern of spatial distribution was highly aggregated and changed towards a regular pattern. Th e age structure of the population also changed along the density diminution, from a predominance of adult individuals to a predominance of juvenile. Moreover, D. antillarum is confirmed as the main herbivore, because when the density of the species was ove r to 0.5 ind/m 2 the cover of macroalgae did not surpass 40%.
In 1983 and 1984, a massive mortality of Diadema antillarum populations occurred i n the Caribbean; the densities were depleted at 93 and 98 %. This event induced changes in the structure and functioning of the coral reefs communities; by causing a phase shift, from reefs dominated by stony coral to macroalgae dominated. In Cuba there is only a report of population status before the event and recent studies are concentrated in the western half of the country. This study characterizes the population of the species westwards of Santa María key. For this, a total of 103 transects were carrie d out, of 20 m 2 each, during three years, between June 2016 and June 2018. A total of 432 records of D. antillarum were obtain, of which 97.16% found protected and 2.84% exposed. The population density suffered a decrease during the three years, caused by significant reduction of the density of adult individuals. This it was reflected in a decrease of the size and the quantity of groups. During the year 2016 the pattern of spatial distribution was highly aggregated and changed towards a regular pattern. Th e age structure of the population also changed along the density diminution, from a predominance of adult individuals to a predominance of juvenile. Moreover, D. antillarum is confirmed as the main herbivore, because when the density of the species was ove r to 0.5 ind/m 2 the cover of macroalgae did not surpass 40%.
Descripción
Palabras clave
Echinoidea, Estructura Poblacional, Herbivoría, Herbivory, Population Structure, Arrecifes Coralinos, Macroalgas