The results are in for the first year of an experimental guinea chick lobster fishery.

And they show that the species' reproduction period extends from May to September with a probable June peak, males grow to be larger than females, and catch rates are higher in the summer and fall and lowest during winter.

The news about the two-year-long experimental fishery, which runs to March, 2000, comes in a report by Fisheries technician and biologist Tammy Trott in the Department of Agriculture & Fisheries' June Bulletin.

The fishery's goal is to collect enough information about the current stocks and biology of the small lobster species so a sustainable commercial fishery can be re-established with a suitable management plan.

Information recorded includes area fished, number of guinea chick lobsters caught, number of berried -- egg-bearing -- females caught plus fish and spiny lobster by-catch.

Where possible, measurements were taken of the trapped guinea chicks and their sex was also recorded.

During the first year of the fishery, which ran from April of last year to March of this year, the four participating fishermen made a total of 6,649 trap hauls.

These yielded 11,119 guinea chick lobsters which means an average of 1.64 guinea chicks were caught each time a trap was hauled -- known as the mean catch per unit effort (CPUE).

A total of 1,238 guinea chicks were measured and sexed and of these 1,124 were male and 114 were female -- a ratio of 9.86 males to each female.

Males ranged in size from 50 to 85 millimetres carapace length while females fell between 49 and 75 millimetres.

Two different traps are being used in the experiment which has a second objective of finding a trap design which will maximise the number of guinea chicks caught and minimise the fish by-catch.

Traps must be used to catch guinea chicks as they are a nocturnal species unlike the spiny lobster.

The Fathoms Plus trap is a lightweight, oval-shaped trap made of black plastic mesh which has been used in the US as a combination trap for crab and lobster.

The A1 trap is rectangular in shape and constructed of galvanised, vinyl-coated one-and-a-half-inch square mesh. Each trap has one purpose-built funnel with a four-inch diameter PVC ring at the inner end.

Figures for the first year show the Fathoms Plus trap had a much lower fish by-catch -- 519 -- than the A1 trap which caught more than five times as much fish -- 2,782.

Other invertebrates snared in the traps include octopus and spiny lobsters, but only 31 spiny lobsters in total were taken.