Introduction

The bluestreak cleaner wrasse Labroids dimidiatus feeds on extenal parasites, diseased and damaged tissues of other fishes – their clients. They are typically territorial around a coral formation termed a ‘cleaning station’ The clients visit the cleaning station and attract the cleaners attention by posing in an unusual position, this communicates to the cleaner that it is safe to clean the client without coming to any harm. The cleaners advertises its services by performing a distinctive ‘dance’. In Indonesia Labroids dimidiatus has over 200 client species, due to this the activity at cleaning stations can be an important indicator of fish assemblages.

Aims

- To determine whether there is any relationship between time spent cleaning by Labroids dimidiatus and size or species of the client fish

- To investigate the presence of a diurnal pattern in the cleaning activity of Labroids dimidiatus

Objectives

- To record time spent cleaning clients of different sizes

- To record the numbers of fish that pose, numbers cleaned and time spent cleaning individuals from various families of client

- To monitor the cleaning activity of one station at different times of the day

Methodology

Using scuba equipment random stations at Sampela, Kaledupa and Home reef were monitored At each I recorded:

- Date
- Time spent at station
- Depth
- Number and approximate age of cleaners at station
- Species of client cleaned
- Size of client cleaned
- Time spent cleaning each individual
- Any species posed but not cleaned

I observed one station at Buoy 2 at 7am, 11am, and 3pm. The number of cleaning events and the number of fish cleaned were recorded over a 35 minute period. This was then repeated three/ four times for each time slot.

Results

My results show that there is a positive correlation between size of client time spent cleaning (see graph below).

If the data is analysed on a family level, the average size of fish for that family plotted against average time spent cleaning gives an R-squared value of 0.77. Time spent cleaning increases with size. For example the average size for a grouper is 34cm, and the average time spent cleaning groupers is 57 seconds, the average size of a damsel fish is 11cm and the average time spent cleaning 6 seconds. The high R- squared value indicates that size is likely to be a more dominating factor for time spent cleaning than species.

My data for species preferences have not yet been tested statistically. The Chromis, Tangs and Triggerfish have the lowest success rate of being cleaned after posing. I do not think however that these differences will be significant.

By eyeballing my data for cleaning activity at different times of the day I think that there is a peak at 7am. This is shown consistently throughout each of the repeats.

Dissemination of results

A dissertation entitled Activity time budgets of the Bluestreak cleaner wrasse will be produced by Kara Davies, University of Aberystwyth by January 2003.