Crea­tures of the coast­line

Ex­pert dis­cusses the Sol­way species

Dumfries & Galloway Standard - - DISTRICT NEWS - Nat­u­ral His­tory So­ci­ety

Marine bi­ol­o­gist Jim Lo­gan gave a lec­ture called Be­tween the Tides.

He aimed to give an over­view of the va­ri­ety of wildlife that can be found be­tween the high and low wa­ter­marks on the Sol­way.

The area is par­tic­u­larly re­ward­ing, partly be­cause of the wide range of habi­tats – from mud­flats through sand and shin­gle beaches to rocky shores – and partly be­cause the tidal range, from six to nine me­tres, is the sec­ond largest in Bri­tain.

Salin­ity can vary con­sid­er­ably, due to streams and rivers that dis­charge into the Sol­way. Mr Lo­gan pointed out that some sea­weeds, for ex­am­ple, can tol­er­ate al­most non-saline wa­ter, and also dry­ing out, whereas oth­ers need a strictly marine en­vi­ron­ment.

Rock pools, which might seem to pro­vide a good place to ob­serve wildlife, can be a dif­fi­cult habi­tat for marine species as in hot weather the pool dries and salin­ity rises, whereas heavy rain will di­lute the sea­wa­ter.

Mr Lo­gan then de­scribed the types of mol­luscs to be found. Th­ese in­clude the lit­tle win­kle, which spends most of its life above the tide­line but takes to the sea to breed, whereas the ed­i­ble win­kle needs daily im­mer­sion in sea­wa­ter.

The fa­mil­iar limpet grips to rocks us­ing a huge foot mus­cle and scav­enges weed by scrap­ing the rock sur­face. Dog whelks feed on other sea crea­tures, such as mus­sels or bar­na­cles, by first drilling a hole in the shell.

The na­tive Euro­pean oys­ter is no longer found on the Sol­way coast, but there is a thriv­ing colony and oys­ter fish­ery in Loch Ryan.

Mr Lo­gan moved on to de­scribe crus­taceans, which range from the large ed­i­ble crab to the tiny pea crab, which lives in­side mus­sels, feed­ing on ma­te­rial gath­ered by its host.

Bar­na­cles, de­spite re­sem­bling small limpets, are in fact crus­taceans which feed on plank­ton by open­ing up plates in the top of the shell.

Other in­ter­tidal crea­tures in­clude starfish, sea anemones and sea urchins. Fish are gen­er­ally ob­served in rock pools and species in­clude the blenny, goby and but­ter­fish, the last named be­cause of its slip­pery skin.

Mr Lo­gan ended by men­tion­ing sea crea­tures that may be­come stranded on the shore. Most no­table were var­i­ous species of jel­ly­fish, some of which were harm­less but oth­ers, such as the lion jel­ly­fish, could in­flict a pow­er­ful st­ing.

The evening con­cluded with a ques­tion and an­swer ses­sion.

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.