Swedish Agency for Marine and Water Management

Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Hummer. Fredningsområde som avelsbank?: Havskräfta.  Mundelarnas byggnad: Stora kräftdjur.  Födointag genom filtrering: Havskräfta.  Bohålsräkning från ytan
Perfomers of environmental monitoring, Government Agencies, Institute of Marine Research.
Perfomers of environmental monitoring, Government Agencies, Institute of Marine Research.
Responsible organisation
1996 (Swedish)Report (Other academic)
Abstract [en]

Har ett hummerfredningområde någon betydelse som avelsbank? Av Mats Ulmestrand, Havsfiskelaboratoriet, Lysekil 

Since 1989 a lobster (Homarus gammarus) fishing area of 1.05 km2 was closed and protected from all fishery except experimental fishery carried out by the Institute of Marine Research in Lysekil. All caught lobster were tagged and released in the area again. This paper gives an estimation of the change in egg production while the fishing mortality on H. gammarus stops. 

Abstract [en]

Mundelarnas funktionella morfologi hos havskräfta. Av Anders Sellbom 

The Norway lobster (Nephrops norvegicus ) can be a suspension feeder, and the lobster use its mouth parts as a "landing-net". A feeding current was produced by the exopodite of the third maxillipeds and with the pleopods. This paper describes the morphology of the mouthparts with respect to suspension feeding. The activity of the mouthparts were tested during aquaria experiments. Crushed shrimps (Pandalus borealis) and nauplii of brine shrimps (Artemia salina) were used asprey. All mouthparts of N. norvegicus are covered with setae in different lenght and size. There are also different shapes among them. In general speaking there are long, serrate setae on the anteriormouthparts and short, stiff setae on the inner mouthparts. Food particles are trapped on the long, serrated setae on the outer mouthparts (mostly the third maxillipeds) and are transported by combing movements of the inner mouthparts to oesophagus.

There was no significant difference in beatspeed of the exopodites. Three different sources were tested against each other: food (crushed shrimp or nauplii of brine shrimp), treatment (before, under and after addition of food) and the interaction food/treatment. Very large variance differences occurred within the same food group when tested for the interaction food/treatment. The explanation is that the exopodites do not beat simultanously and there are large speed differences between left and right exopodite. A two factor ANOVA analysis of variance was used as a statistic method. 

Abstract [en]

Olika aspekter på suspensionsätning hos tre decapodarter från svenska västkusten av Daniel Valentinsson, Havsfiskelaboratoriet, Lysekil

Suspension feeding in adults of the edible crab Cancer pagurus (118-295 g) and the squatlobster Galathea strigosa (22-29 g) was tested in experiments offering planktonic food items of about 600 mm size measuring the clearing capacity. Both species were found to significantly clear the water of food particles comprising nauplii of the brine shrimp Artemia salina. Food intake was verified with stomach analysis. In another experiment it was investigated if the ability to suspension feed is different between the sexes in the Norway lobster Nephrops norvégiens, and if the clearance rate is dependent on the concentration of food items. No difference between the sexes was found. Neither was any difference in clearance rate depending on the food concentration found. The significance of the ability to suspension feed in larger decapods is discussed regarding the species ecological roles.

Place, publisher, year, edition, pages
Göteborg: Fiskeriverket , 1996. , p. 45
Series
Information from the Institute of Marine Research, Lysekil 1988-1997, ISSN 1100-4517 ; 1996:2
Keywords [en]
lobster, fishery, mortality, mouthparts, suspension feeding
Keywords [sv]
hummer, havskräfta, avel, föda, fiske, dödlighet, mundelar, suspensionsätning
National Category
Fish and Aquacultural Science Environmental Sciences
Research subject
Finance, National; Environmental Objectives, A Rich Diversity of Plant and Animal Life
Identifiers
URN: urn:nbn:se:havochvatten:diva-394OAI: oai:DiVA.org:havochvatten-394DiVA, id: diva2:1512424
Available from: 2020-12-23 Created: 2020-12-23 Last updated: 2020-12-23

Open Access in DiVA

fulltext(14642 kB)130 downloads
File information
File name FULLTEXT01.pdfFile size 14642 kBChecksum SHA-512
631b20056d0fc9395bf3701964fb2f2917de0b0bf7506c49eef18e924ac7be3c8b61e08c80d9bc19d840f4e05f7591f2e1ced611c4e94e947c1ae06ea03aa2bf
Type fulltextMimetype application/pdf

By organisation
Institute of Marine Research
Fish and Aquacultural ScienceEnvironmental Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 130 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 386 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf