First indications of autumn migration routes and destination of common minke whales tracked by satellite in the North Atlantic during 2001-2011

ABSTRACTWe use biochemical, biological, archaeological, and historical analysis to examine relationships between Atlantic cod migration, sea temperature, and shifts in the distribution and occupancy of historical fishing sites in Iceland during the last millennium. Results support the hypothesis that the cooling climate of the North Atlantic during the period commonly referred to as the Little Ice Age coincided with changes in Atlantic cod migration patterns. Historical analysis shows a concomitant increase in reports of worsening Atlantic cod fishing and a severe decrease in domestic fishing, particularly in north Iceland. We conclude that Atlantic cod fisheries in Iceland originally thrived because of the proximity to cod migration routes. However, despite the mobility of local fishers, fluctuations in fish migrations, coupled with a harsher climate and increased competition for fishing grounds, resulted in a stagnation that lasted until the eventual modernization of the fishery in the mid-nineteenth century.

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Origin of freshwater fauna of the North-Atlantic islands: present distribution in relation to climate and possible migration routes

SIL Proceedings 1922-2010 ◽

10.1080/03680770.2005.11901995 ◽

2005 ◽

Vol 29 (1) ◽

pp. 198-203 ◽

Cited By ~ 1

Author(s):

Gísli Már Gíslason

Keyword(s):

North Atlantic ◽

Migration Routes ◽

The North ◽

Present Distribution ◽

Freshwater Fauna ◽

The North Atlantic

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Changes in blood testosterone and progesterone concentrations of the North Atlantic minke whale (Balaenoptera acutorostrata) during the feeding season

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f03-159 ◽

2004 ◽

Vol 61 (2) ◽

pp. 230-237 ◽

Cited By ~ 13

Author(s):

Matthías Kjeld ◽

Árni Alfredsson ◽

Örn Ólafsson ◽

Morten Tryland ◽

Ivar Christensen ◽

...

Keyword(s):

Frequency Distribution ◽

North Atlantic ◽

Minke Whale ◽

Balaenoptera Acutorostrata ◽

Hunting Season ◽

P Values ◽

The North ◽

Minke Whales ◽

The North Atlantic ◽

Cyclic Changes

An opportunity to study seasonal changes of sex hormones in the North Atlantic minke whale (common minke whale, Balaenoptera acutorostrata) arose when we obtained access to fresh postmortem blood samples from 104 females and 83 males. The whales were caught in the North Atlantic during MaySeptember 19921995. Serum progesterone (P) and testosterone (T) concentrations were measured and compared with anatomical data. The frequency distribution of female serum P values showed two clusters, one consisting mainly of immature animals and the second of pregnant ones, with mean serum values of about 0.49 ± 0.04 (SE) and 44.2 ± 2.84 nmol·L1, respectively. The frequency distribution of male serum T did not show any group-specific distribution during the hunting season. The mean serum T value for the males was 0.63 ± 0.13 nmol·L1. Contrary to earlier reports on the Antarctic minke whale (Balaenoptera bonaerensis), serum T values rose during the hunting season in mature males (p < 0.0001). Serum P values in immature females increased during the season (p = 0.015). This increase agrees with the predominantly annual reproduction cycle of minke whales. Blood sex hormone measurements seem to be useful for detecting cyclic changes and pregnancy of minke whales.

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