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Introduction. The nationwide Icelandic Cancer Registry (ICR) was established in 1954 and has been extensively used for research from the outset although formal quality assessment of the registry database has not previously been undertaken. In this paper we report the fi rst formal evaluation of the comparability, validity, timeliness and completeness of the ICR. Material and methods. Data from the ICR for the period 1955-2009 (41 994 cancer diagnoses) were used, applying established quantitative and semi-quantitative methods. In order to evaluate the completeness of the ICR, record linkage was performed between the ICR and the population-based Hospital Discharge Registry to identify potential missing cases for tumour diagnoses in 2000 and 2001. Results. The registration is in accordance with internationally accepted standards. It has high validity, but random variation in rates is prominent in this small population. Record linkage with the Hospital Discharge Registry revealed that in addition to the 2459 cancers registered in 2000-2001, 21 cases were missing, indicating 99.15% completeness. Tumours of the central nervous system constituted 71%, and haematological malignancies 19% of these missing entries. Discussion. The ICR has high completeness, validity and timeliness and is comparable to the cancer registries of the other Nordic Countries. As cancer registries have many important roles, it is of great importance that their data are at all times as complete and valid as possible. Thus the ICR aims to constantly improve and update the data gathering process.

We consider combinations of three types of control measures for the management of fisheries when the input information for policy decisions is uncertain. The methods considered include effort controls, catch quotas and area closures. We simulated a hypothetical fishery loosely based on the Icelandic cod fishery, using a simple spatially explicit dynamic model. We compared the performance with respect to conserving the resource and economic return for each type of control measure alone and in combination. In general, combining more than one type of primary direct control on fishing provides a greater buffer to uncertainty than any single form of fishery control alone. Combining catch quota control with a large closed area is a most effective system for reducing the risk of stock collapse and maintaining both short and long-term economic performance. Effort controls can also be improved by adding closed areas to the management scheme. We recommend that multiple control methods be used wherever possible and that closed areas should be used to buffer uncertainty. To be effective, these closed areas must be large and exclude all principal gears to provide real protection from fishing mortality.

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Despite their economic importance, the ecology of many sea cucumber species is poorly understood and factors influencing their habitat preferences remain largely unexplained. The distribution and habitat preference of two sea cucumber species;Holothuria atraandHolothuria eduliswere studied off the north-west coast of Sri Lanka by underwater visual census in October 2008. The relationships between the density of each species and the habitat variables, such as mean grain size, organic content (% of dry weight), gravel (%), silt–mud (%), and depth, were examined using a generalized additive model. All these variables except silt–mud have significant influence (P < 0.05) on the habitat association ofH. atra. The shallow water (<10 m) seagrass habitat with sediments characterized by 2–3.5% organic content, 15–25% of gravel and coarse sand (0.7–1.2 mm) were the most preferred conditions byH. atra. High densities ofH. eduliswere found in the shallow (<10 m) depths of rocky areas with algae and seagrass. Favoured bottom sediment conditions ofH. eduliswere mainly similar to the conditions preferred byH. atra, except organic content which did not significantly influence the habitat preference of this species. The preference towards the specific habitat characteristics seems to be associated with their feeding and protection. An understanding of habitat preference would be useful to improve the management of these sea cucumber populations and enable more precise stock assessment.