Predation
and dispersal of Parah tree (Elateriospermum tapos) seeds by red spiny
rats (Maxomys surifer) in Khao Nan National Park, Thailand
A.
Charoensuk, F.W. Tina, M. Jaroensutasinee* and K. Jaroensutasinee
Center of
Excellence for Ecoinformatics, School of Science, Walailak University, Nakhon
Si Thammarat - 80161, Thailand
*Corresponding
Author E-mail: mullica.jn@gmail.com
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Key
words
Elateriospermum tapos seeds
Red spiny rats
Scatter hoarding
Seed predation and dispersal
Publication Data
Paper received :
09.02.2017
Revised received : 01.06.2017
Accepted : 07.09.2017
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Abstract
Aim: Seed predation and
dispersal by scatter-hoarding rodents are important for plant population
dynamics and forest structure. In this study, the potential of red spiny rats
(Maxomys surifer) as predators, dispersers and scatter-hoarders of
Parah (Elateriospermum tapos) seeds was examined in Khao Nan National
Park, Thailand.
Methodology:
One
thousand Parah seeds and 100 rats were used in this experiment. Ten seeds
with one rat were set inside a cage. Infrared videos of seed predation and dispersal
by the rats were made from 9:00-10:00 p.m. afterwards, the numbers of seeds
predated (predated, undamaged, and partially predated), dispersed
(non-removed, displaced and removed) and scatter-hoarded were recorded.
Results:
The
percentage of undamaged, predated and partially predated seeds, as well as of
removed, non-removed, and displaced seeds differed significantly. In both
males and females, most of the seeds were undamaged, followed by those
predated and partially predated. Additionally, most of the seeds were not
removed, followed by those removed and displaced. Both males (35%) and
females (37%) scatter-hoarded seeds, and the seed numbers did not differ
between sexes. Body weight of rats was positively correlated with the
percentage of predated seeds and negatively correlated with the percentage of
undamaged seeds, but not with the potentially viable, non-removed, displaced,
or removed seeds.
Interpretation:
Red
spiny rats act as predators, dispersers and scatter-hoarders of Parah seeds.
It indicates that these rats may play an important role in Parah population
dynamics.
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