Studying Beaked Whales entangled in Tuna nets in the northwest Indian Ocean.

Beaked Whales, Ziphiidae, spend the majority of their time in deep oceanic waters, spending most of their lives beyond the continental shelves, and little at the surface. This makes them one of the least well-understood groups of Cetaceans, or Mammals of any kind. Some species have few, if any, sitings ar sea, being known almost exclusively from bodies washed ashore in varying states of decomposition. Because of this, the taxonomy of Beaked Whales is less well-established than is the case for most Mammal groups, with new species and nomenclature revisions being published every few years. 

Studying Whales caught as bycatch offers a cost-effective way to study poorly understood Cetacean populations, providing insights into populations which can help shape conservation policies. Such data collection is often accomplished by training fishermen themselves as citizen scientists. Drift gillnets are widely used many parts of the world to target Tuna, but are also noted for the large amount of large-Vertebrate bycatch they produce. In the northwest Indian Ocean drift gillnets are widely used by the fishing fleets of Iran and Pakistan, presenting a threat to Whales in this area, but also presenting an opportunity for scientists to gather data on these Animals.

In a paper published in the journal Zoology in the Middle East on 13 February 2025, Muhammad Shoaib Kiani of the Institute of Marine Science at the University of Karachi, Mohsen Rezaie-Atagholipour of the Qeshm Environmental Conservation Institute, Rab Nawaz and Muhammad Moazzam of the World Wide Fund for Nature - Pakistan, Bushra Shafiq also of the  Institute of Marine Science at the University of Karachi, Haleh Ali Abed of the Midaf Nature Conservation Society, and Koen Van Waerebeek, also of the Qeshm Environmental Conservation Institute and of the Centro Peruano de Estudios Cetológicos, present the results of a long-term study of Beaked Whale entanglements in Tuna gillnets in Iranian and Pakistani waters.

A citizen science program was established in Pakistan in 2012, in which fishermen on pelagic gillnet Tuna vessels were trained to collect data on Cetacean bycatch. In Iran reviews of mass media at local and national levels, looking for Cetacean-related stories, have been carried out since 2018, and a series of interviews of fishermen was carried out in 2022.

Kiani et al. discovered eight incidents in which entangled Cetaceans could be identified as Beaked Whales in the waters of the Gulf of Oman and Arabian Sea, two in Iranian territory, five in Pakistani territory, and one in international waters.

The first recorded incident happened on 10 February 2015, when fishermen on board the Pakistani vessel Al-Azaan discovered a live Beaked Whale caught in a gillnet they had deployed 95 km to the west of the Swatch (the undersea canyon formed where the Indus River enters the ocean) and 177 km off the coast of Sindh, an area where the seafloor is about 1.5 km deep. 

Based upon video evidence, this Whale was estimated to be 5-6 m long, and slender with a slightly protrudent melon (mass of adipose tissue on the forehead), and a long snout without protruding teeth. This Animal lacked the scars associated with tooth-raking typically seen in male Beaked Whales, and is therefore assumed to have been a female.

The Whale had a brownish-grey dorsal surface, slightly paler on the head, and had a large, Dolphin-like fin about two thirds of the way along its body. This is, along with its location in the tropical Indian Ocean, is considered to be consistent with a Longman’s Beaked Whale, Indopacetus pacificus. This species was first described in 1928 from the skull of a Whale found in Queensland Australia in 1882, with a second skull being found on the shore of Somalia, East Africa, in 1955. For a long time, these two specimens were all that was known of this species, however, recent studies have established that Whales washed up on the shores of the Philippines, Maui (Hawaii), Taiwan, Myanmar, the Andaman Islands, South Africa, and Japan, previously identified as Southern Bottlenose Whales, Hyperoodon planifrons, were in fact Longman’s Beaked Whales, and based upon this data, 65 sightings of live Whales in the  Indian and Pacific oceans have been assigned to the species.

The Whale encountered by the Al-Azaan became entangled in a net as it was being retrieved, allowing the crew to release it without apparent harm by cutting away part of the net. This process took about 30 minutes, and while the Whale is thought to have been unharmed, one of the fishermen received minor injuries.

(a)-(h). Successive steps in gillnet disentanglement operation of a Longman’s Beaked Whale, Indopacetus pacificus, in Pakistani waters. Note the head with moderately bulbous melon (e), (h), long rostrum (f), (g), (h) tubular in dorsal view (h), limited linear scarring (e) and large falcate dorsal fin (f, g). Selected frames were taken from a video. Kiani et al. (2025).

The second recorded incident happened on 31 March 2017, when an un-named Pakistani vessel encountered a 4 m long Whale 383 km off the coast of Pakistan, again in the Swatch area, an area where the sea slightly more than 3 km deep. 

This Whale had a distinct, but non-bulbous melon, a long slender snout, and a low, sub-triangular dorsal fin. The skin of the Whale was a uniform grey, slightly darker towards the tail, and it had no visible scarring of any type. It was not possible to identify this Whale to species level, but it was probably a member of the genus Mesoplodon, possibly Deraniyagala’s Beaked Whale, Mesoplodon hotaula, or Ginkgo-toothed Beaked Whale, Mesoplodon ginkgodens, although this species has never been recorded in the Indian Ocean, or even Ramari’s Beaked Whale, Mesoplodon eueu, although this species tends  to lighten towards the tail, and is a cold-water species, never previously recorded in the western Indian Ocean north of Mozambique. 

The third incident was recorded in August 2017, when a fisherman from Bandar-e-Konarak on the coast of Sistan and Baluchestan Province, Iran, sent a video to the Iranian National News Agency, IRIB News, showing a Whale entangled in a gill net. This incident is thought to have happened in the waters of Iran’s Exclusive Economic Zone, and probably close to Bandar-e-Konarak. 

The Whale could be seen to blow, suggesting that it was alive and breathing. It appears to be a Beaked Whale with no visible teeth. The bulbosity of the melon cannot be determined from the video. The fluke (tail) of the Whale can be seen, and from comparison to the arm of a fisherman, is estimated to be between about 140 cm wide, which would equate to a Whale 4.7-4.9 m in length. The fluke also lacks a median notch, confirming that the Animal is a Ziphiid.

An unidentified middle-sized Beaked Whale, with a melon of unclear bulbosity, net-entangled within Iran’s Exclusive Economic Zone waters off Sistan and Baluchistan Province, northern Gulf of Oman, in August 2017. (a), (b) Flukes without central notch and tailstock; (c) the only registered blow and vague view of the head. Both Mesoplodon sp. and Indopacetus pacificus would be possible. Kiani et al. (2025).

The fourth incident occurred on 18 January 2018, when a small-to-medium sized Beaked Whale was recorded trapped in gillnet 474 km from the coast of Pakistan, an area where the sea is slightly under 3.2 km deep. This Whale was 3.5-4.5 m long, with a medium length snout and a non-bulbous melon and no central notch on its fluke; its colour and/or markings could not be determined due to poor light. This is consistent with it being a member of the genus Mesoplodon. The Pakistani fishermen who encountered this Whale were able to disentangle it from their nets, and report if swam away in good condition. 

The fifth incident occurred on 19 March 2019, when two Beaked Whales, interpreted as a mother and calf, became entangled in the same gillnet off Churna Island, 96 km from the coast of the Pakistani Mainland. The waters here are shallow, at 295 m.

The calf was described as the size of an adult Common Bottlenose Dolphin, making it 3.0-3.5 m in length, while it was not possible to estimate the size of the larger Whale. The smaller Whale had a dark grey upper surface,  and a whitish underside. It had a short snout, and no sign of a bulbous melon, its dorsal fin hooked, no notch could be seen in the tail. These Whale are also interpreted as belonging to the genus Mesoplodon. The fishermen reported successfully disentangling both Whales.

The sixth recorded incident happened in February 2022, when Iranian fishermen reported encountering a Whale caught in a drift gillnet 1300 km off the coast of Bandar-e-Beris in eastern Sistan and Baluchestan Province. Video footage of the incident shows a medium-sized Beaked Whale with a medium-length Dolphin-like beak, and a non-steeply sloping melon, consistent with a member of the genus Mesoplodon. The video also shows that the Whale has two apical or slightly sub-apical mandibular teeth, indicating that it was male, as well as a dark eye-patch, an almost straight mouth, and a small, slightly hooked tail. The length of the Whale is uncertain, but it appears to be about 4.5-5.5 m.

An unidentified Mesoplodon sp. bycaught in far offshore waters of the northern Arabian Sea, 1300 km from Bandar-e-Beris at the eastern side of Iran’s Sistan and Baluchestan Province, in February 2022. (a), (c) Two erupted (sub)apical mandibular teeth indicate an adult male. (b) Dolphin-like, medium-length rostrum, gently sloping melon and smallish dorsal fin. Kiani et al. (2025).

The final incident happened in early June 2023, when a large Beaked Whale became entangled in a drift gillnet in the coastal Iranian Gulf of Oman, about 37 km from the port of Chabahar in eastern Sistan and Baluchestan Province. This Animal was clearly an adult male, with numerous took-rake scars and erupted apical teeth. It was estimated to have been 5.8-6.0 m in length, with an erect, Dolphin-like dorsal fin, and way brownish grey in colour with a lighter head. This is interpreted as being consistent with either a Longman’s Beaked Whale, Indopacetus pacificus, or a Cuvier’s Beaked Whale, Ziphius cavirostris. 

An adult male Beaked Whale being liberated after accidental entanglement in Tuna gillnet in coastal waters of the Gulf of Oman, some 37 km from Chabahar, Iran, in early June  2023. (a) Large body size with two erupted teeth at the apex of the mandibula; (b) a tall, erect, falcate, Dolphin-like dorsal fin, a moderately long and well-defined rostrum; (c) with numerous tooth rakes on anterior body; and (d) some degree of bulbosity in the melon. The morphology of the Beaked Whale is congruent with Indopacetus pacificus, but Ziphius cavirostris cannot be excluded. Kiani et al. (2025).

The first of these incidents is regarded as the first record of Longman’s Beaked Whale, Indopacetus pacificus, in Pakistani waters, with incidents five and seven representing potential additional sightings. A beached individual assigned to the species was recorded in Gujarat State, India, in 2014, making the Pakistan entanglement the second record of the species in the northwest Indian Ocean. Previously a skull has been recorded from the coast of Somalia in 1955, a member of the species was sighted from Socotra Island, Yemen in 1971, and another in the waters of the southern Bay of Bengal in 2009. Five Longman’s Beaked Whales have been recorded as bycatch from Sri Lanka, although these have been disputed, and fourteen sightings and a stranding recorded from the Maldives. 

Incidents two, four, six, and possibly five represent the first records of Mesoplodon sp. in Iranian and Pakistani waters, although none of these specimens could be confidently identified to species level. 

Drift gillnets are considered to be one of the most significant anthropogenic threats to Whales, although evidence to support this is absent in many areas. Kiani et al.'s study shows entanglement is a clear threat to Beaked Whales in the northwestern Indian Ocean, as while all of the reported Whales were freed, it is likely that a greater number of Whales were not released safely, and therefore not reported.

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Photolateralis polyfenestrus: A new species of Ponyfish from the Gulf of Oman.

Ponyfish, Leiognathidae, are small, silvery, laterally compressed Perciforme Fish found in brackish and marine waters around the Indian and western Pacific oceans. Like many Perciformes they have locking spines on their fins, which serve as a defence against predators; locking these spines may not deter the predator from swallowing a Ponyfish, but stand a significant chance of causing the Ponyfish to lodge in the predator's throat and choking the predator. Ponyfish also possess a second defence not found in other Perch, in the form of light organs on their underside which host bioluminscent Bacteria, helping to camouflage them against the sky when seen from below.

In a paper published in the American Museum Novitates on 19 June 2019, John Sparks of the Department of Ichthyology at the American Museum of Natural History, and Prosanta Chakrabarty of the Museum of Natural Science at Louisiana State University, describe a new species of Ponyfish from the Gulf of Oman.

The new species is placed in the genus Photolateralis, on the basis of a translucent midlateral flank stripe, which is unique to this genus, and given the specific name polyfenestrus, meaning 'many windows', in reference to the translucent midlateral windows, which are rounded and appearing spotlike. The species is known only from a single specimen acquired at Mutrah Fish Market in northeastern Oman. This specimen is male, 66.8 mm in length, with two rows of teeth on both the upper and lower jaws. It is is distinguished from congeners by the presence of a short, composite midlateral stripe comprised of three small, rounded translucent windows that are peppered with chromatophores (colour cells).

Photolateralis polyfenestrus, male, 66.8 mm; Gulf of Oman, Mutrah Fish Market. Specimen has a field tag on posterior flank and anteriormost midlateral window is obscured behind pectoral-fin rays in image. Sparks & Chakrabarty (2019).

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Landslide kills three in the Amhara Region of Ethiopia.

Three people have died following a landslide at Jan Amora area of the Amhara Region of Ethiopia on Monday 16 September 2019. The three dead are reported to all be members of the same family, with the youngest being an eighteen-month-old toddler. This is the latest in a series of fatal landslides in the Amhara Region over the past two months, linked to the exceptionally heavy rains falling across northern Ethiopia. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.

 

The approximate location of the 16 September 2019 Jan Amora landslide. Google Maps.

The landslides have been caused exceptional rainfall in the mountains of Ethiopia this year, which has in turn been caused by high temperatures over the Gulf of Oman, leading to higher levels of evaporation there. High levels of evaporation in the Gulf of Oman leads to more rainfall in Ethiopia, and higher waters on the River Nile, and recent years have seen a series of exceptionally hot summers in the region, with consequent increases in flooding and water born disease along the course of the Nile.

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Sixty two known deaths in flooding in Sudan.

Sixty two people are now known to have died, ninety eight have been injured, and around 200 000 have been driven from their homes in a series of floods across Sudan this month. Seventeen of the country's eighteen provinces have been effected by the floods, which have swept away at least 35 000 houses and caused severe damage to the country's already week infrastructure. There are now fears that standing water may lead to outbreaks of water-born diseases such as Cholera or Malaria.

Flooding in the town of Wad Ramli in northern Khartoum State. EPA.

The majority of the flooding has been caused by high waters on the River Nile, following exceptional rainfall in the mountains of Ethiopia this year, which has in turn been caused by high temperatures over the Gulf of Oman, leading to higher levels of evaporation there. High levels of evaporation in the Gulf of Oman leads to more rainfall in Ethiopia, and higher waters on the River Nile, and recent years have seen a series of exceptionally hot summers in the region, with consequent increases in flooding and water born disease along the course of the Nile.

A road washed away by flooding outside of Omdurman. Sudan Daily.

Many areas away from the Nile have been effected by flash flooding. Like many desert areas, arid parts of Sudan, while generally arid, is prone to occasional severe flooding. This stems from two causes; firstly the arid climate prevents the development of a thick soil layer which would be expected in less dry areas, so that in much of the area (non-porous) bedrock is either exposed or close to the surface, and secondly the hot climate leads to heavy evaporation from nearby seas and oceans, so that if the wind changes direction and brings water-laden air to the area, it brings a lot of precipitation with it. This combination of heavy rainfall and low ground absorbency leads to large amounts of water at the surface, typically moving downhill at some speed. Wadis, dry channels or ravines through which these sudden floods are channelled, can be particularly dangerous at these times, particularly as they often appear to resemble natural pathways or even camp sites to people unfamiliar with the climate.

A flooded village in Sudan. Athavan News.

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Hottest full day on Earth ever recorded in Oman.

The city of Quriyat on the north coast of Oman recorded the highest sustained temperature over a single day on Wednesday 26 June 2018, when the temperature remained at 42.6°C for the entire 24 hour period, or more precisely, for a 51 hour period that included the entire day. This is some way short of the highest temperature recorded on the Earth, 58°C at El Azizia in Libya on 13 September 2012, but is potentially more harmful to Human life as the sustained temperature prevents cooling of and recovery from heat damage. The record beats a previous hottest day also recorded in Oman, at Khassab Airport, where the temperature remained at or above 41.9°Cfor the entire of 27 June 2011.

The city of Quriyat in Oman, where the highest sustained temperature over a 24 hour period on Earth was recorded on 26 June 2018. Andries Oudshoorn/Wikimedia Commons.

The high temperatures are linked to the proximity of the Gulf of Oman, an enclosed body of water which can become extremely heated compared to the rest of the Indian Ocean, raising the temperature of the air above and around it. This is contrary to what we normally expect from a maritime climate, where the thermal inertia of the sea (requiring much more energy to heat or cool it than the atmosphere) tends to have a moderating effect on the climate, leading to cooler summers and warmer winters,

The location of the city of Quriyat. Google Maps.

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Fizesereneia panda, a new species of Gall Crab from the Red Sea.

Gall Crabs, Cryptochiridae, are small Crabs which live in burrows within living Corals, causing the Coral to grow around the living Crab. Most species live in tropical reef Corals, where some can reach very high population densities, though some are known from deep water Corals. Gall Crabs are known to have a global distribution, probably occurring wherever there are Corals, but have only been extensively studied in a few areas where specialists on the group have worked, with additional records from other parts of the world collected as parts of more general biological surveys.

In a paper published in the journal Zootaxa on 16 March 2015, Sancia van der Meij of the Department of Marine Zoology at the Naturalis Biodiversity Center, Michael Berumen of the Red Sea Research Center of the King Abdullah University of Science and Technology and Gustav Paulay of the Florida Museum of Natural History at the University of Florida, describe a new species of Gall Crab from the Saudi Arabian Red Sea and reefs in the Gulf of Oman.

The new species is placed in the genus Fizesereneia, and given the specific name panda in reference to its colouration; whitish with two black blotches on its back which resemble the eye patches of a Giant Panda. The species is described from twelve female and one male specimens collected from the Farasan Banks and Islands and the reefs off Thuwal on the Saudi Arabian Red Sea coast and one male and one female from off Bandar Al-Khayran in the Gulf of Oman.

Fizesereneia panda, colouration in life. (A, B) female in dorsal (A) and ventral (B) view. (C, D) male in dorsal (A) and ventral (B) view. Arthur Anker & Patrick Norby in van der Meij et al. (2015).

These showed very little variation in size with females being 4.2-4.3 mm in length and 3.4-3.6 mm in width, and the males 4.2 mm in length and 3.2 mm in width. The colouration was more variable, with the white areas of some specimens being more bluish than in others, while the red areas were more reddish in some specimens. The male from the Arabian coast was reddish in colour, the male from the Gulf of Oman had blue and green spots.

Fizesereneia panda, female (left) and male (right) specimens in dorsal view. Erik-Jan Bosch in van der Meij et al. (2015).

This is the first record of the genus Fizesereneia from the Red Sea or Gulf of Oman, the genus has previously been recorded from Vietnam, Indonesia, Japan, Australia, and Micronesia. Like all previous members of the genus it was found on Corals belonging to the Family Lobophylliidae, and also like most other members of the genus it seems to be slightly flexible about host, being found on two species of Lobophyllia in the Red Sea and on the closely related Symphyllia recta in the Gulf of Oman (a species which has not been found in the Red Sea to date); most other genera of Gall Crabs produce species specific to a single Coral host.

Fizesereneia panda (circled) in Lobophyllia corymbosa at Shi'b Ammar on the Farasan Banks on the Red Sea Coast of Saudi Arabia. Sancia van der Meij in van der Meij et al. (2015).

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A new species of Gall Crab from Indonesia and Malaysian Borneo.

Gall Crabs, Cryptochiridae, are colony-forming Crabs inhabiting Coral reefs. They dwell in tunnels within the Coral surface, often at very high population densities, the females causing the Corals to form galls (tumour-like growths) which they use for protection.

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