Netherlands 



139 



available; small boats and outboard motors; 40 ft 

 LOA, Max W^ebei: 



INSTRUCTIONAL PROGRAM: Summer courses of about 

 two weeks length in marine ecology and hydrography ; 

 courses at Den Helder in comparati\e physiology and 

 general invertebrate zoology; thesis research for stu- 

 dents of Dutch universities. 



SIZE OF STAFF: Nine or 10 at professional level; 12 

 technicians. 



important specills available for laboratory 

 studies: 

 Coelenterata: Five species of medusae 

 Polychaeta: Thirty-five species of polychaetes 

 Crustacea: Carcinus maenas, Cancer pagiirt/s. E/i pa- 

 gurus bernhardus, Crangon sp. 

 Cephalopoda: Sepia officinalis 



Echinodermata: Asterias rubens. Psaunnechinus 

 miliar is 



MAJOR CURRENT RESEARCH PROJECTS AND SCIENTIFIC 

 LEADERS: 



Chemical hydrography (K. Postma) 

 Dissolved organic matter (E. K. Duursma) 

 Periodicity (J. W. de Blok) 

 Migration problems ( F. Creutzberg) 

 Underwater sound (W. H. Dudok van Heel) 

 Population dynamics (J. Westenberg) 

 Physiology of molluscan pumping (A. Dral) 

 Ecology and behavior of invertebrates (J. Verwey) 

 PUBLICATIONS ISSUED: None directly. Annual reports 

 of the station appear in Archives Neerlandaises de 

 Zoologie. From 1961 results of research at the station 

 appear in The Netherlands Journal of Sea Research. 



Rijksinstituut roar Visserijonderzoek 



NETHERLANDS INSTITUTE FOR FISHERY INVESTIGA- 

 TIONS 



POSTAL address: 



Headquarters: Postbus 68, IJmuiden, Nederland 



(Netherlands). 

 Field Station: Wemeldinge (Zeeland), Reepweg, 

 Stormezandepolder. 

 EXECUTIVE officer: Professor Dr. P. Korringa, Di- 



recteur. 

 SPONSORING AGENCY: Ministerie van Landbouw en 

 Visserij (Ministry of Agriculture and Fisheries). 



YEAR FOUNDED: 1888. 



SCOPE OF ACTIVITIES: Restricted research on fisheries 

 including biological, microbiological, chemical, and 

 hydrographical investigations. 



SEASON OF OPERATION: All year. 



PHYSICAL ENVIRONMENT ACCESSIBLE: North Sea 

 (sandy beaches), Wadden Zee (high salinity, tidal 

 flats and creeks, strong currents), IJsselmeer (eutro- 

 phic lake) ; estuarine conditions at Zeeland Field Sta- 

 tion, eutrophic slightly brackish canals and smaller 

 lakes. 



PROVISIONS FOR VISITING SCIENTISTS: Space for 1-2 

 visitors at headquarters, 1 at Zeeland Field Station ; 

 fees not usually charged; living quarters available 

 nearby. 



MAJOR RESEARCH FACILITIES: Moderately complete 

 library; running sea and fresh-water, small aquarium 

 tanks, direct supply of high salinity seawater and large 

 outdoor oyster pond at Zeeland Field Station; research 

 collections of fauna and flora available at Rijksmuseum 

 Van Natuurlyk Historic, Leiden (State Museum of 

 Natuial History, Leiden) ; machine and wood shop, 

 electrical and electronic shop, skilled shop workman 

 available; vessels, 34 m LOA, Willem Beukelsz, and 

 12 m LOA dredge boat as well as various inspection 

 vessels on the IJsselmeer and Wadden Zee. 



SIZE OF STAFF: Thirteen at professional level; 20 tech- 

 nicians. 



IMPORTANT SPECIES AVAILABLE FOR LABORATORY 



STUDIES: 



Crustacea: Crangon riilgare 



Moliusca: Mytilus edulis, Ostrea edulis 



Pisces: Esox lucius, Anguilla vulgaris, Solea vulgaris, 



Pleuronectes platessa. Clupea harengus, Ammodylus 



ntarinus 

 MAJOR CURRENT RESEARCH PROJECTS AND SCIENTIFIC 



LEADERS: 



Herring stCKk versus herring fishery (J. J. Zijistra) 

 Herring behavior and herring fishery (K. Postuma) 

 Herring larvae and herring stock (J. J. Zijistra and 



K. Postuma) 

 Plaice stock fluctuations and plaice fishery (L. K. 



Boerema and J. de Veen) 

 Whiting stock and whiting fishery (M. Roessingh) 

 Serological background of fish populations (W. de 



Ligny) 

 Eel stock and eel fishery and production biology (C. 



Deelder) 

 Hatchery problems in pike and pike-perch (J. Wil- 



lemse) 

 Shrimp stock and shrimp fishery (R. Boddeke) 

 Productivity of fresh water bodies and fish stock (R. 



Th. Roskam and J. Willemse) 



RI JKSINSTITUUT VOOR VISSERIJONDERZOEK, I)MUIDEN 



