Solar storms may trigger sperm whale strandings: explanation approaches for multiple strandings in the North Sea in 2016

AbstractThe Earth's atmosphere and the Earth's magnetic field protects local life by shielding us against Solar particle flows, just like the sun's magnetic field deflects cosmic particle radiation. Generally, magnetic fields can affect terrestrial life such as migrating animals. Thus, terrestrial life is connected to astronomical interrelations between different magnetic fields, particle flows and radiation. Mass strandings of whales have often been documented, but their causes and underlying mechanisms remain unclear. We investigated the possible reasons for this phenomenon based on a series of strandings of 29 male, mostly bachelor, sperm whales (Physeter macrocephalus) in the southern North Sea in early 2016. Whales’ magnetic sense may play an important role in orientation and migration, and strandings may thus be triggered by geomagnetic storms. This approach is supported by the following: (1) disruptions of the Earth's magnetic field by Solar storms can last about 1 day and lead to short-term magnetic latitude changes corresponding to shifts of up to 460 km; (2) many of these disruptions are of a similar magnitude to more permanent geomagnetic anomalies; (3) geomagnetic anomalies in the area north of the North Sea are 50–150 km in diameter; and (4) sperm whales swim about 100 km day−1, and may thus be unable to distinguish between these phenomena. Sperm whales spend their early, non-breeding years in lower latitudes, where magnetic disruptions by the sun are weak and thus lack experience of this phenomenon. ‘Naïve’ whales may therefore become disoriented in the southern Norwegian Sea as a result of failing to adopt alternative navigation systems in time and becoming stranded in the shallow North Sea.

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New sperm whale remains from the late Miocene of the North Sea and a revised family attribution for the small crown physeteroid Thalassocetus Abel, 1905

Comptes Rendus Palevol ◽

10.5852/cr-palevol2021v20a39 ◽

2021 ◽

Author(s):

Apolline ALFSEN ◽

Mark BOSSELAERS ◽

Olivier LAMBERT

Keyword(s):

North Sea ◽

Late Miocene ◽

Sperm Whale ◽

Close Relative ◽

Sperm Whales ◽

The North ◽

The Family ◽

The North Sea ◽

Early Radiation ◽

The One

In spite of a continuously expanding physeteroid fossil record, our understanding of the origin and early radiation of the two modern sperm whale families Kogiidae Gill, 1871 (including the pygmy and dwarf sperm whales, Kogia spp.) and Physeteridae Gray, 1821 (including the great sperm whale, Physeter Linnaeus, 1758) remains limited, especially due to the poorly resolved phylogenetic relationships of a number of extinct species. Among those, based on fragmentary cranial material from the late early to middle Miocene of Antwerp (Belgium, North Sea basin), the small-sized Thalassocetus antwerpiensis Abel, 1905 has been recognized for some time as the earliest branching kogiid. The discovery of a new diminutive physeteroid cranium from the late Miocene (Tortonian) of Antwerp leads to the description and comparison of a close relative of T. antwerpiensis. Thanks to the relatively young ontogenetic stage of this new specimen, the highly modified plate-like bones making the floor of its supracranial basin could be individually removed, a fact that greatly helped deciphering their identity and geometry. Close morphological similarities with T. antwerpiensis allow for the reassessment of several facial structures in the latter; the most important reinterpretation is the one of a crest-like structure, previously identified as a sagittal facial crest, typical for kogiids, and here revised as the left posterolateral wall of the supracranial basin, comprised of the left nasal (lost in kogiids for which the postnarial region is known) and the left maxilla. Implemented in a phylogenetic analysis, the new anatomical interpretations result in the new Belgian specimen and T. antwerpiensis being recovered as sister-groups in the family Physeteridae. Consequently, the geologically oldest kogiids are now dated from the Tortonian, further extending the ghost lineage separating these early late Miocene kogiid records from the estimated latest Oligocene to earliest Miocene divergence of kogiids and physeterids.

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Large amounts of marine debris found in sperm whales stranded along the North Sea coast in early 2016

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2016.08.027 ◽

2016 ◽

Vol 112 (1-2) ◽

pp. 134-141 ◽

Cited By ~ 38

Author(s):

Bianca Unger ◽

Elisa L. Bravo Rebolledo ◽

Rob Deaville ◽

Andrea Gröne ◽

Lonneke L. IJsseldijk ◽

...

Keyword(s):

North Sea ◽

Marine Debris ◽

Sperm Whales ◽

The North ◽

The North Sea ◽

Sea Coast ◽

North Sea Coast

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Stranding of Two Sperm Whales (Physeter macrocephalus) in the “North Sea Trap” at Henne Strand, Denmark

Aquatic Mammals ◽

10.1578/am.42.1.2016.35 ◽

2016 ◽

Vol 42 (1) ◽

pp. 35-41 ◽

Cited By ~ 3

Author(s):

Mette S. Hansen ◽

Aage K. O. Alstrup ◽

Jørgen H. Hansen ◽

Mohammad N. S. Al-Sabi ◽

Bettina Nonnemann ◽

...

Keyword(s):

North Sea ◽

Physeter Macrocephalus ◽

Sperm Whales ◽

The North ◽

The North Sea

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Space weather effects on drilling accuracy in the North Sea

Annales Geophysicae ◽

10.5194/angeo-23-3081-2005 ◽

2005 ◽

Vol 23 (9) ◽

pp. 3081-3088 ◽

Cited By ~ 14

Author(s):

S. J. Reay ◽

W. Allen ◽

O. Baillie ◽

J. Bowe ◽

E. Clarke ◽

...

Keyword(s):

Magnetic Field ◽

External Field ◽

North Sea ◽

Survey Method ◽

Magnetic Observatory ◽

Magnetic Survey ◽

Earth’S Magnetic Field ◽

The North ◽

Earth's Magnetic Field ◽

The North Sea

Abstract. The oil industry uses geomagnetic field information to aid directional drilling operations when drilling for oil and gas offshore. These operations involve continuous monitoring of the azimuth and inclination of the well path to ensure the target is reached and, for safety reasons, to avoid collisions with existing wells. Although the most accurate method of achieving this is through a gyroscopic survey, this can be time consuming and expensive. An alternative method is a magnetic survey, where measurements while drilling (MWD) are made along the well by magnetometers housed in a tool within the drill string. These MWD magnetic surveys require estimates of the Earth's magnetic field at the drilling location to correct the downhole magnetometer readings. The most accurate corrections are obtained if all sources of the Earth's magnetic field are considered. Estimates of the main field generated in the core and the local crustal field can be obtained using mathematical models derived from suitable data sets. In order to quantify the external field, an analysis of UK observatory data from 1983 to 2004 has been carried out. By accounting for the external field, the directional error associated with estimated field values at a mid-latitude oil well (55° N) in the North Sea is shown to be reduced by the order of 20%. This improvement varies with latitude, local time, season and phase of the geomagnetic activity cycle. By accounting for all sources of the field, using a technique called Interpolation In-Field Referencing (IIFR), directional drillers have access to data from a "virtual" magnetic observatory at the drill site. This leads to an error reduction in positional accuracy that is close to matching that of the gyroscopic survey method and provides a valuable independent technique for quality control purposes.

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