Loading...
Publication
Visual signalling and sexual selection in male fiddler crabs Uca tangeri
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 676.98 KB | Adobe PDF |
Advisor(s)
Abstract(s)
Similar to many other species of fiddler crabs, the interactions of Uca tangeri are influenced
by 2 characteristic visual signals: the waving display performed by males with their enlarged
claw, and the building of structures (mudballs) around the burrow entrance. This study focused on male
signalling, male-male competition and female mate choice Female choice and male mating success
were investigated by looking at male quality, male visual signals (waving activity and mudballs) and
male interactions and their outcome. Fieldwork was carrled out In June and July 1997 at the Ria Formosa
Natural Park, Algarve, Portugal, on a sandy beach with an average population density of
2.06 burrows m-2. Behavioural observations of focal males were made at low tide, 1 h before and after
the peak of low tide, that is during the mudballing phase or interaction phase. This was also when measurements
of male characteristics, mudballs and burrow charactelistics were taken. The results show
that the quality of a male's burrow IS related to its depth, and depth is correlated with 4 features: claw
size, waving rate, mean dlstance to mudballs and number of mudballs. Therefore, females could use
these features as Indicators of gallery depth, eliminating the need to enter the burrow for sampling.
Males compete for the possession of burrows that are more vlslted by females, thus taking over burrows
is an alternative strategy to burrow digging Male waving activity, mudball distance and claw size can
be considered as multiple visual signals available to females for mate choice. Females' first choice cntenon
would seem to be burrow quality.
Description
Keywords
Fiddler crabs Visual signals Male competition Mate choice Burrows
Citation
Marine Ecology Progress Series, 189, 233-240