Printer Friendly

Glorious gobies live in rock poo s: A guide to the little fish that ols around the coast OFWALES; Gobies are small, pretty, carnivorous fish that have a weak suction cup formed by the fusion of their pelvic fins that they attach to the sand. They can be spotted by families hunting in rock pools around Wales. But there is still plenty to find out about our Welsh gobies, as Paul Kay and Lin Baldock explain.

Byline: Paul Kay and Lin Baldock

GOBIES are small marine fish and there are about 17 species of gobies found around the coasts of Britain and Ireland. Most of these have been recorded from the Welsh coasts.

Whilst some are abundant and common in suitable habitats, only a few are easily identifiable. With the use of high-resolution underwater digital photography, this situation is changing.

We have been photographing gobies for a number of years and are confident that the vast majority can be identified from digital images providing that key features are captured.

Most gobies are bottom dwelling for much of the time, with a few exceptions. As some are curious, they can be photographed relatively easily. A few species are usually seen swimming but even these will rest on, or in, the seabed at times.

Of these, it is the transparent and crystal species which are hardest to photograph, as they are, as their names suggest, difficult to focus on - especially so when they are flitting about in mid-water.

It is difficult to be definitive about the ecology and behaviour of some of the gobies, as is the case for many marine species found in Welsh waters; we still lack a lot of information about them.

Breeding Male gobies generally choose a nest site and then attract females to it.

Black gobies, for example, will often select an old shell, or perhaps a discarded tin and will then carefully attach the eggs on the inside surface and continue to protect them from predators until they hatch.

Other natural nest sites might be narrow crevices in rocks or under boulders, with the eggs laid on the 'ceiling' to avoid them being swamped by silt.

Male black gobies adopt different mating tactics, perhaps dependent on their size. Large males, distinguished by their greatly elongated fin rays, guard a nest to which females are attracted; these are called parental males. By contrast smaller males, which lack such a long fin ray and closely resemble females in colour, may sneak into guarded nests and attempt to fertilise eggs as they are laid - sneaker males.

These small males do not guard nests. Similar sneaking behaviour has been recorded for the common goby.

Colour Gobies are very variable in colour. They are experts in camouflage and can match their colour to blend with the habitat.

Colour also depends on numerous other factors such as mood: fish displaying during the breeding season show dramatic colour changes which can last only a few seconds.

Colours at night differ from those recorded during the day. While colour has often been used as a guide to identify fish, in the case of gobies it is not always a reliable tool due to its ability to change colour and emphasis of pattern.

Black goby - Gobi du The black goby is a silver-grey to black fish with coarse speckling and blocks of black or dark brown colour along its flanks. Scales on the head are not usually visible.

Both dorsal fins have dull red and brown zig-zag stripes and flecks and, particularly in large adult males, the first three fin rays of the first fin can be elongated and swept back in graceful curves.

The fish look solidly built with heavy 'shoulders', tapering abruptly from the pectoral fins to the tail. Breeding males may be black all over (hence the name) but this colour is not often seen in the field. Black gobies can be very common over rocky mixed ground or on muddy sediment, where they may even use burrows if no other shelter is available.

They can be found from low tide level to considerable depths in sheltered to exposed habitats. Black gobies are very common in Holyhead Harbour, for example on the muddy sediment off Newry Beach and small 'gangs' of them roam around Cardigan Bay. They have been likened to jackdaws in that they travel in foraging and interacting gangs.

The Rock goby - Bili bigog This goby differs from the black goby by having silky free rays at the rear of the pectoral fin, usually visible in good photographs. They also have he top of the of the first er, yellowish at least in well-defined scales on thhead, and the top edge dorsal fin is often a lighteor even orangey colour, Breeding males.

intertidally depths of 20 cky seabed. Menai Strait suspension ily revealed Rock gobies are found and subtidally down to dmetres or more on rocThey are common in the Maround the area of the bridge and are most easby torchlight at night.

likely to be ock pools or ally in the nto shallow k goby's dise laid interwater under able rocks, ded by the This is the goby most found on the shore in rounder boulders, especispring when they come iwater to breed. The rock tinctive pointed eggs are tidally and in shallow wboulders and small stawhere the eggs are tendmales.

oby - Gobi Leopard spotted go mannog This is a distinctive gosteely grey-blue body over with bold orange to coloured spots.

oby with a marked all o chocolate ry dark and with black btidal rocky Older fish can be vermight then be confused gobies. Crevices in subreefs on moderately exposed to exposed shores from about 5m depth downwards are the preferred habitat for this species.

This habitat preference explains why this goby was not recognised as a member of the UK fauna until as late as the 1950s. The dredging methods used at the time to collect fish did not sample this habitat effectively and it was not until scuba diving became widely used that it was realised that this is actually a relatively common goby in some areas.

Painted/Common/Sand/Loza-noi goby complex The gobies in this group can be diffi-cult to tell apart!

Painted gobies - Gobi lliwgar They are extremely common and may be seen as they dart and dash around on muddy, sandy and mixed grounds.

They are very curious and will approach divers to investigate what goodies the divers might have stirred up. This goby has a brightly coloured first dorsal fin with double transverse rows of black spots, and males have an electric blue margin to the fin. Juveniles tend to occur in midwater shoals in late summer and early autumn, together with twospotted gobies. Males will aggressively defend their nests and often develop bold colour marks when approached by a diver.

Common goby - Gobi These gobies are very similar in appearance to sand gobies but have more of a snub nose and are found in shallow, near-shore, often estuarine habitats.

Common gobies do occur together with sand gobies in some areas, making it difficult to distinguish the species. Breeding males can display very colourful dorsal fins with a series of transverse rosy bands.

Sand gobies - Gobi y tywod This name actually includes two species which occur in Welsh waters: the Sand goby and Lozanoi's goby. The species hybridise with each other which complicates identification. These gobies are very common subtidally extending into deep water on sandy, muddy, mixed sediment.

Two-spotted goby - Gobi brych Whilst most goby species tend to be bottom dwelling, large mid-water shoals of milling two-spotted gobies can often be seen in sheltered waters and rock pools.

This goby is very common in shallow weedy habitats over rock, especially from mid-summer onwards, and its behaviour contrasts with other gobies as it is usually seen above rather than on the seabed. When water temperatures drop in winter, these gobies can be found lying on sediment seabeds or in shallow rock crevices and may have very different colouration from that shown in summer; this behaviour and colour can confuses divers.

Diminutive goby - Gobi bach These very small (2cm long) gobies are almost certainly under-recorded in Wales. A recent record made by divers from Pembrokeshire, who photographed one during a Seasearch dive, may well be the first photographic evidence of the species in Welsh waters.

Not a great deal is known about this tiny fish which is actually bigger than Guillet's goby, for which there appear to be no obvious Welsh records, although it almost certainly lives around the Welsh coasts: Guillet's goby is often found in Horse Mussel beds and these do occur off the north Llyn Peninsula.

Transparent - Gobi tryloyw and Crystal goby - Gobi gwydraidd Transparent gobies are reported to occur in Welsh waters and have been photographed in Tremadog Bay but they are probably under-recorded and may well be reasonably common. Both these species tend to be nocturnal which probably explains why they are seldom seen by divers. Furthermore, both are relatively delicate, so when netted they are apt to be easily mangled and may go unnoticed in the catch which again does not help recording their presence.

Jeffrey's - Gobi Jeffreys and Fries' goby - Gobi fries These two gobies have been caught occasionally in deeper waters off Wales: so far no records have been made by divers.

CLIMATE CHANGE VISITORS Climate change is already affecting sea temperatures and consequently some significant changes are happening to the distribution and abundance of marine life in Welsh waters. This is also likely to affect gobies. Here are three 'rare' species which might arrive in our waters: Couch's goby - Gobi Couch Certainly a possibility in the shallow, warm waters of Tremadog Bay, in particular on Sarn Badrig.

Giant goby - Gobi mawr The nearest records for this species are from the Scilly Isles. It is an intertidal species in the UK, occurring in high rock pools with lots of green algae.

Redmouth goby - Gobi Mingoch There are no British records for this species but it does occur in a range of sheltered to exposed habitats on the south and west coast of Ireland.

Paul Kay and Lin Baldock have been photographing and researching into gobies throughout the UK and Ireland for the past few years and have taken many thousands of photographs of these fish. Dr Lin Baldock is an experienced marine biologist and Paul Kay is co-author of A Fieldguide to the Marine Fishes of Wales and adjacent waters.

This article appeared in Natur Cymru quarterly magazine.

CAPTION(S):

Fries's goby <B

Jeffrey's goby

Diminutive goby

Transparent goby

Two-spotted goby guarding eggs

Male painted goby

Leopard spotted goby

Rock goby

Black goby photographhed in Cardigan Bay

Paul Kay
COPYRIGHT 2014 MGN Ltd.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2014 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:Features
Publication:Western Mail (Cardiff, Wales)
Geographic Code:4EUUK
Date:Sep 23, 2014
Words:1708
Previous Article:Happiness actually begins at 70, new report suggests.
Next Article:Climate change on back burner.

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters