Endangered whales live in area earmarked for gas exploration
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RISSO'S DOLPHINS
view moreCREDIT: LEONIDAS KARANTZAS/GREENPEACE
Endangered whales and dolphins live year-round in an area of the Mediterranean earmarked for oil and gas exploration, new research shows.
Various cetacean species are known to inhabit the Hellenic Trench off Greece in the summer, but until now little has been known about their winter whereabouts.
This lack of information has been used to justify seismic surveys (which may harm whales and dolphins) in winter.
The new study found that at least four species – including the regionally endangered sperm whale – live in the deep waters of the Hellenic Trench in both summer and winter.
The research was carried out in 2021-22 by the Greenpeace Research Laboratories, University of Exeter, Greenpeace Greece and the Pelagos Cetacean Research Institute.
“The Mediterranean is one of the busiest seas on the planet, and whales and dolphins are already threatened by ship strikes, overfishing, bycatch (accidental catching), pollution with chemicals and plastics, and climate change,” said Dr Kirsten Thompson.
“Noise is also a key threat. Certain whale species, for example the Cuvier’s beaked whales, are known to be particularly vulnerable to human-made noise, which comes from sources including ship engines, military sonar and ‘air guns’ used to survey for oil and gas.
“These combined threats could affect populations of whales and dolphins that rely on the Hellenic Trench as key habitat.
“The shallower waters of the Hellenic Trench have been designated as an Important Marine Mammal Area. Based on our findings, it is clear that seismic surveys and oil and gas extraction across the Trench would be completely at odds with conservation.”
Co-author Dr Alexandros Frantzis, Scientific Director of Pelagos Cetacean Research Institute, said: “We have already shown that ship-strikes alone will drive the eastern Mediterranean population of sperm whales to extinction in a few decades, if no measures (shipping lanes and/or creation of Areas to be Avoided) are taken along the Hellenic Trench.
“For nine years, we have been trying to convince the Greek authorities to address this problem in collaboration with the International Maritime Organisation, with no concrete results.
“On the other hand, the local population of Cuvier’s beaked whales, after decades of repeated mass strandings due to military sonar use, are declining as well as the striped dolphins that inhabit the Hellenic Trench.
Risso's dolphins
CREDIT
Leonidas Karantzas/Greenpeace
“Seismic surveys and gas and oil exploration in the area will be the ‘coup de grace’ for the local cetacean populations if added to the already existing anthropogenic pressures and threats.”
Kostis Grimanis, of Greenpeace Greece, added: "This important research demonstrates clearly that endangered whales and dolphins live year-round in an area of the Mediterranean of huge ecological importance.
“The choice to follow through with oil and gas drilling in those waters will not only be detrimental to our collective fight against the climate crisis but also to our collective efforts to conserve and protect those iconic species of marine biodiversity.”
The researchers used two Greenpeace vessels to carry out visual and acoustic surveys of large areas of the Hellenic Trench, including two blocks that are earmarked for seismic surveys and potential oil and gas exploration (west Crete and south-west Crete).
The area may also be affected by a proposed new gas pipeline called EastMed, which would connect eastern Mediterranean gas reserves to Greece.
Using sightings and computer analysis of audio recordings, the research team confirmed the presence of endangered sperm whales, Cuvier’s beaked whales (classified as “vulnerable” in the Mediterranean), Risso’s dolphins, striped dolphins and rough-toothed dolphins.
They confirmed a further 224 recordings of unidentified dolphins (several dolphins have similar vocalisations, so it is not always possible to distinguish between them).
The paper, published in the journal Endangered Species Research, is entitled: “Summer and winter surveys of deep waters of the Hellenic Trench, Greece, provide insights into the spatial and temporal distribution of odontocetes.”
JOURNAL
Endangered Species Research
SUBJECT OF RESEARCH
Animals
ARTICLE TITLE
Summer and winter surveys of deep waters of the Hellenic Trench, Greece, provide insights into the spatial and temporal distribution of odontocetes
ARTICLE PUBLICATION DATE
26-Oct-2023
Early whaling eradicated species from local waters
The right whale and grey whale were eliminated from the eastern Atlantic centuries before the age of industrial whaling began
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THESE ARE AMONG THE 719 WHALE BONES FROM VARIOUS MUSEUM COLLECTIONS IN EUROPE THAT WERE ANALYSED BY ARCHAEOLOGISTS. MOST OF THE WHALE BONES ORIGINATED FROM AROUND 900 BCE TO 1500 CE.
view moreCREDIT: PHOTO: NTNU UNIVERSITY MUSEUM
The industrial whaling of the 19th and 20th centuries almost wiped out several species. However, even though whaling took place on a much smaller scale before this period, it was enough for at least two species to disappear completely from European waters.
These two species used to be among the most common, but now one of these species is on the verge of extinction.
“Whaling was widespread from a very early time. This had major consequences for species in Europe,” says Youri van den Hurk, a former postdoctoral fellow at the Norwegian University og Science and Technology (NTNU) University Museum.
Studying whale bones
A group of archaeologists examined 719 whale bones from various museum collections in Europe. Most of the whale bones originated from around 900 BCE to 1500 CE.
By studying the proteins in this bone material, it is often possible to find out which species these bones originated from. Youri van den Hurk carried out much of the analysis work at the NTNU University Museum.
The whale bones examined originated from whales caught as far north as Norway and as far south as Spain. Whaling was practised by people from many European countries, both in Scandinavia and the British Isles, but also in Belgium, France and Spain.
Coastal species disappeared first
It is perhaps not surprising that whaling was so widespread. Everything from a whale weighing several tonnes had a use.
Meat and blubber were eaten, whale oil was used to light lamps, and whale bones were made into everything from corsets to houses to trinkets. There were many products.
“Historical sources show that the earliest whalers used harpoons with buoys attached to them. This enabled them to tire the animals out before using spears and lances to kill them. However, the methods may have varied from place to place. Sources from Norway mention that spears tipped with poison were used, or that hunters cornered whales by chasing them into fjords,” says van den Hurk.
During the most intensive period, however, whalers occasionally caught so many whales that they only took the most valuable parts. The rest was left to rot.
In the 19th Century, larger whaling ships and more efficient equipment made it possible to catch more and larger whales in less time. Even the gigantic blue whale and fin whale could now be caught.
Modern ships enabled whalers to travel to distant regions of the Arctic and Antarctic. Norwegians Erik Eriksen and Svend Foyn’s grenade harpoon was particularly effective, and management of the whale stocks was usually very poor.
Both of the species that disappeared early from Europe are whales that stay close to the shore. This means it was possible for people in small boats and with ordinary harpoons to hunt them, even before whaling became a major industry. These whales were therefore particularly vulnerable, even though whaling was taking place on a very small scale.
“We know little about the aims and scope of this pre-industrial whaling. However, archaeology and historical sources give us a valuable opportunity to find out more about this early whaling,” says van den Hurk.
The grey whale survived in the Pacific Ocean
The grey whale (Eschrichtius robustus) is one of the species from which scientists find a lot of bones in their material. One of the bones is from Trondheim.
“The large prevalence surprised us, because grey whale bones have not been commonly identified in such large numbers during previous studies,” says Professor James H. Barrett, a professor at the Department of Archaeology and Cultural History.
The grey whale started disappearing from parts of the North Atlantic as early as the Middle Ages, and the species was completely gone from the area by the 18th Century. The species currently has two viable populations in the Pacific Ocean, but it has not yet returned to the Atlantic with the exception of the occasional stray.
Despite us no longer seeing grey whales along the Norwegian coast or elsewhere in Europe, the species survived in areas where whaling was not that common at the time.
Another species fared a lot worse, however, and the scientists knew about the problems it faced before this study got underway.
The North Atlantic right whale is still struggling
The North Atlantic right whale (Eubalaena glacialis) is a slow swimmer that prefers to stay close to the shore. In addition, the species has a large amount of blubber, which keeps it afloat on the surface of the water when killed.
“The species is therefore relatively easy prey for whalers. This is probably why North Atlantic right whale bones make up most of the material we find,” says Professor Barrett.
North Atlantic right whales were widespread along the coast of Europe until the 18th Century, but have hardly been hunted since the 19th Century because so few of them were left. Today, North Atlantic right whales are probably extinct in the eastern Atlantic, and hardly any of them are left in the western Atlantic. The species is in serious trouble.
North Atlantic right whales have been completely protected since 1937, but despite this, only 300–400 individuals remain. These are mostly found along the coast of North America.
Today, whaling no longer poses a threat to North Atlantic right whales. However, in a world of eight billion people, these are not good times for a species that lives in coastal areas where there is a lot of shipping traffic.
Several species are almost extinct
During the course of 70 years, 1.3 million whales were killed in Antarctica alone. Whaling declined after the 1960s because whales became scarce and hunting them was no longer profitable.
The blue whale, once common in Norway, is a famous example of how wrong things went. One of the only places in Norwegian waters where blue whales can be seen today is off the coast of Jan Mayen, and these sightings are very rare.
Approximately 300,000 blue whales could be found in Antarctica before the onset of modern whaling. Although the species was protected as early as 1966, ships from the Soviet Union continued to hunt it for a long time. Currently, there are certainly no more than 25,000 blue whales left in the world, perhaps as few as 10,000, divided into several subspecies.
A total ban on whaling was only introduced in 1982. Despite this prohibition, Norway, Japan and Iceland continue their whaling activities, with Japan and Norway often citing research as an alibi.
Norwegian whalers have killed at least 15,000 minke whales since 1982, but the local population amounts to approximately 100,000 animals and is not considered endangered. Despite the prevalence of this species, this whaling sometimes sparks strong criticism from other countries.
Norwegian whaling is currently very limited, but whale meat is still a common sight in Norwegian freezer counters.
Can the grey whale make a comeback?
We can certainly learn something from these findings.
“What I find particularly interesting and useful is that the grey whale and North Atlantic right whale were so widespread in Europe, perhaps the most common groups we had, and both were completely eradicated locally,” says van den Hurk.
However, lone grey whales have been spotted again in Europe. Could it be that the species is making a comeback?
“Climate change has led to the Northwest Passage being ice-free for longer periods than previously. This makes it possible for grey whales to return to the North Atlantic. The Northwest Passage is the sea route between Asia and Europe, located to the north of North America. Seeing as we now know where the species used to be prevalent, we also know which areas we need to protect if the grey whale ever returns,” says van den Hurk.
International collaboration
The work was led by NTNU, but has been carried out in collaboration with the University of Cambridge, the University of Oviedo, the University of Groningen, Leiden University, the University of York, the University of Rennes, Accueil Ecole, Oniris and the Arctic University Museum of Norway. The results have now been presented in the Royal Society Open Science journal.
The research was funded by the European Research Council (ERC), the EU’s Horizon 2020 programme and the Royal Netherlands Academy of Arts and Sciences.
References: Van den Hurk Y et al. 2023 The prelude to industrial whaling: identifying the targets of ancient European whaling using zooarchaeology and collagen mass-peptide fingerprinting. R. Soc. Open Sci. 10: 230741. https://doi.org/10.1098/rsos.230741
JOURNAL
Royal Society Open Science
METHOD OF RESEARCH
Observational study
SUBJECT OF RESEARCH
Not applicable
ARTICLE TITLE
The prelude to industrial whaling: identifying the targets of ancient European whaling using zooarchaeology and collagen mass-peptide fingerprinting
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