NEW
PAPER: Encouraging encounters:
unusual aggregations of bowhead whales Balaena mysticetus in the western
Fram Strait
Dear Colleagues,
I am pleased to announce the following paper recently published in Endangered Species Research
De Boer MN, Janinhoff N, Nijs G, Verdaat H (2019) Encouraging
encounters: unusual aggregations of bowhead whales Balaena mysticetus in
the western Fram Strait. Endang Species Res 39:51-62.
Abstract
The subpopulation of the bowhead whale Balaena
mysticetus in the East Greenland-Svalbard-Barents Sea is endangered and
until recently was believed to number in the tens. Recent studies have
suggested that this subpopulation appears to be increasing. Here, we report on unusual
aggregations of bowhead whales within the Fram Strait. We present opportunistic
and effort-corrected observations of bowhead whales made from a small
expedition vessel during cruises in June (2015−2018). Bowhead whales were
sighted on 85 occasions (220−227 whales). An aggregation in 2015 (n = 84
whales) and high numbers in 2018 (n = 104−110) exceeded all previous records.
The index of whale abundance was significantly higher in open water-leads (1.08−1.14
whales km−1 of survey effort) compared to areas with drift-ice (0.51−0.53
whales km−1). The highest abundance index was measured in deep waters where the
bottom slope was relatively steep.
Our findings highlight
the temporal and spatial consistency of this species in areas with relatively
loose ice cover (open water-leads) and steep slopes. It is unknown how global warming
and resultant changes in ice-extent are going to affect bowhead whales within
the Strait and whether they will find new feeding grounds due to an expanding
open-ocean habitat. These slopes may become increasingly important to bowhead
whales and Arctic top predators as a spring/early summer feeding ground. These
relatively large numbers of bowhead whales are encouraging and can help direct
future research monitoring programs to study the population ecology of these
endangered whales.
The paper is Open Access
and can be downloaded from Endangered Species Research:
Kind Regards,
Wageningen Marine Research, Den Helder, Netherlands