The accurate recording of data is an essential part of any scientific study. In studies of fish it is also important to record data with the minimum stress to the fish. Using our system sampling and data collection can be accomplished by an individual. However, a partner enabling one person to net and one to record data can be fun and make things easier.

Our sampling methods are designed to keep fish in an aquatic environment except for short periods of transfer using soft nets.  After netting and the removal of weed and rubbish from the sorting bin the captured fish will be visible.  First identify any fish that are used in recreation or commercial fisheries, record their numbers and length, and release. These fish will generally be juveniles.  They may belong to groups such as leatherjackets where at certain times of the year juveniles are common in shallow water. The juveniles of many fish species are difficult to identify and with these species their family and numbers should be recorded.

Most of the inshore demersal fish will be from a few common species although their abundance may vary seasonally.  Use your aquarium net to remove these fish individually beginning with the most common species.  For most fish check their identification and measure their length in the net and then release. If you want to have a longer look at a fish for identification place it in a ziplock bag with water where it can be viewed for some time without stress. Record the name of each species and their lengths on the record sheet.

Some fish are better measured in a measuring trough.  Measuring troughs are designed to encourage fish to lay supine between layer of cushioning sponge.  Make sure that the sponge is wet and cool with sea water before measuring fish.

The sex and reproductive state of some species can be ascertained.  For instance mature male pipefish can be identified by a the presence of a brood pouch.

We have picked a LOCATION for sampling. A location is a place such as Marion Bay, Yorke Peninsula. 

It is good if we record the latitude and longitude of the location as there may be more than one Marion Bay, or it may not appear on larger scale maps. At the location there may be different HABITATS such as deep water headland, shallow seagrass areas, and areas of moderate depth. These are SITES that we may decide to sample.

To sample these sites we have to decide what SAMPLING METHODS we are going to use, for instance; HAND NETTING in the shallows, SNORKELLING, LINE FISHING, or SCUBA DIVING. What sampling method we use and what site we sample depend on whether we are TARGETING particular species or types of fish, or targeting particular habitats, sites, or locations. In cases other than for vouchered specimens, specimens and data should be collected in a manner which does not harm the fish and then released at the site where they were found.

HAND NETTING: works great to sample shallow inshore areas of low wave action with weedy bottoms. Many sedentary species can be captured in numbers, then identified, measured and released unharmed. When hand netting after identification of undersized juveniles of any recreational or commercial fish species immediately release them. Take a quick note of the species, approximate size, sexual status (with adult pipefish sex and egg number). To hand net effectively, you need a plastic tub with a rope to attach it to your waist, a hand net with small mesh.

The record sheet can be carried with you or kept with your gear on the beach. Pick a spot where the weed beds can be accessed. The type of record sheet (see the bottom of this page, provided as html and MS word tables) will depend on the extent of the project but the minimum should be the location, site, date, species, depth - high tide, type of substrate and vegetation.  That is where they are above or close to low tide mark, and preferably where they are close inshore, in channels, or adjacent to rocks.  This situation means that if desirable you can easily return to the shallows to sort and record your catch.

Line fishing with light tackle (2-3kg line and a 12-14 hook) and a tub with water for the fish is the best way to sample gobies, blennies, small wrasse, and many other rock or weed fish in rocky pools or crevices. These fish are fast and very difficult to hand net. The barb on the hook should be crimped with pliers to minimise damage to the fish. As for hand netting you will need a tub with water to swing the fish into. Many fish will not be hooked and are just hanging onto the bait. However, they will often hang on long enough to reach the tub.

SNORKELLING: is particularly good in shallow rocky or shelly bottoms, or rock pools for species which will not take baits, where hand nets get caught or damaged. A small hand net will enable the capture of many species, or behavioural and ecological notes can be taken on site.

The sampling method will also affect the NUMBER of fish we can capture for IDENTIFICATION, MEASUREMENT, or in special cases for VOUCHER in museums where they will be given an ACCESSION NUMBER (i.e. SAM 4950 = South Australian Museum specimen number 4950). Vouchered specimens can be used for later confirmation of the accuracy of identification, for molecular studies, to enable later identification of difficult species, or in being new and unique to a location, or they may be invaluable for other future studies (changes in pollution, disease, genetics etc.).