United Nations recognises three conservation projects as new World Restoration Flagships.

The United Nations has recognised three conservation projects as World Restoration Flagships, according to a press release issued by the United Nations Environment Program on 4 December 2025. World Restoration Flagships are projects intended to have large-scale and long-term impacts, held up as examples which embody the 10 Restoration Principles of the UN Decade on Ecosystem Restoration (2021–2030). World Restoration Flagships already cover an area of over 10 million km², an area larger than China.

The first new project recognised is the Shellfish Reef Building Program in Australia. This project, a partnership between the Nature Conservancy and the Australian Government, aims to restore reefs of Oysters and Mussels which were once found around much of the southern coast of Australia but which have been greatly depleted by over-harvesting, sedimentation and pollution.

Globefish amongst Mussels and restored shellfish reef in Dromana, Port Phillip Bay. Jarrod Boord/Streamline Media in Reef Builder (2024).

Since its inception in 2020, the Reef Builder Program has worked with local communities to restore reefs at thirteen locations along the southern coastline of Australia; it aims to restore 30% of Australia's original shellfish reefs by 2030. The project has generated over 425 jobs, and about US$10 million in income for over 50 small and medium sized businesses, as well as helping local communities to reconnect to nature and promote stewardship over the natural environment.

The second project recognised is the Respectful Returns Initiative in Canada, a partnership between Parks Canada and local and Indigenous communities, which aims to restore damaged rivers and streams in seven national parks along Canada’s Pacific and Atlantic coasts. 

Salmon being released into the Bay of Fundy as part of the Respectful Returns Initiative. Parks Canada.

Since its initiation in 2010, the Respectful Returns Initiative has restored over 650 km² of land and 228 km of waterways, created over 100 jobs, supported research projects by three universities, and formed partnerships with 32 local organisations and community groups. The Salmon population has increased at six of the seven locations where the Initiative works. The Initiative aims to both protect Salmon and to strengthen the connection between the population and their environment. 

The third project recognised is the Thicket Restoration Movement in South Africa, a collaboration uniting over 60 initiatives in Eastern and Western Cape provinces, which aims to restore over 8000 km² of indigenous subtropical thicket by 2030.

Replanting a Kuzuko Thicket in South Africa. AfriCarbon. 

These thickets serve as a grazing resource for both wild Mammals and livestock, particularly under drought conditions, which is an important consideration following the drought of 2023/4, which is the worst the region has suffered in over 100 years. It is a particularly important resource for threatened species such as Black Rhinoceros and African Bush Elephant, and is also a significant carbon reserve, with soils covered by thicket retaining notably more carbon than exposed soils. It is estimated that restoring these thickets sequesters around eight million tonnes of carbon dioxide per year. The project is also predicted to directly create over 1000 jobs in rural communities, as well as improving the lives of around two million people.

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Oxynoemacheilus kottelati: A new species of Stone Loach from the Aegean drainage of Anatolia.

Stone Loaches of the genus Oxynoemacheilus are found across the Eastern Mediterranean, the southern Caucasus, Anatolia, Mesopotamia, and Central Iran. To date, 67 species have been assigned to the genus, of which are found in Turkish inland waters, and 36 entirely endemic to the country. Sixteen species are found within the Tigris and Euphrates basins, 14 within rivers and streams draining into the Mediterranean, six in rivers and streams draining into the Black Sea, four in rivers and streams draining into the Caspian, two species within the Konya Basin, two within the Marmara Basin, and one within the Van Basin. 

In a paper published in the journal Zoosystematics and Evolution on 9 May 2024, Davut Turan of the Faculty of Fisheries at Recep Tayyip Erdoğan University, Sadi̇ Aksu of the Vocational School of Health Services at Eskişehir Osmangazi University, Sali̇m Serkan Güçlü of the Faculty of Eğirdir Fisheries at Isparta University of Applied Sciences, and Gökhan Kalaycı, also of the Faculty of Fisheries at Recep Tayyip Erdoğan University, describe a new species of Oxynoemacheilus from streams in the Aegean drainage of Anatolia.

The new species is named Oxynoemacheilus kottelati, in honour of the Swiss ichthyologist Maurice Kottelat, for his contributions to our understanding of the world's Fish fauna. The species is described from a series of Fish collected from the Havran and Karınca streams in Balıkesir Province, Turkey, in October 2023.

Oxynoemacheilus kottelati FFR 15655, (a), (b) Holotype, male, 47 mm; FFR 15656; (c) Paratype, female, 49 mm; Türkiye, Balıkesir Province, Havran Stream. Turan et al. (2024).

Specimens of Oxynoemacheilus kottelati range from 35 to 54 mm in length, with a deep body, laterally compressed at the base of the tail. They have a marbled brownish pattern on their flanks and dorsal surface, but are white on the underside. 

Oxynoemacheilus kottelati, FFR 15657, paratypes: (a) male, 47 mm; (b)female, 46 mm; (c) male, 45 mm; Havran Stream; FFR 15656; (d) female, 48 mm; Karınca Stream; Türkiye, Balıkesir Province. Turan et al. (2024).

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Assessing the impact of predation on birth size in marine Snakes.

Moving from one environment to another exposes organisms to new selective pressures on life histories, and where multiple organisms from related lineages make the same transition, it presents an opportunity for biologists to analyse these pressures. For example, Squamates (Snakes and Lizards) which migrate from warm environments to cooler ones frequently switch from egg-laying to bearing live young, while Birds making the same transition tend to produce smaller clutches of eggs.

Birth size is considered to be a fundamental life-history trait, subject to a number of evolutionary pressures. Where intraspecific competition is low, smaller birth sizes are often a result, as offspring survival is not dependent on size at birth. Conversely, larger birth size can be driven by a number of factors, for example a lack of small prey can drive up birth size in species where the young must hunt for themselves, as only larger neonates are able to capture enough prey to survive. 

The shift from a terrestrial habitat to a marine one presents organisms with a variety of different challenges, including thermal regimes, oxygen availability, light levels, ocean currents, types of predators, prey, competitors and pathogens. Nevertheless, the marine environment clearly presents opportunities for terrestrial Tetrapods, with numerous lineages of Mammals, Reptiles, and even Birds having made the transition. Elapid (Front-fanged) Snakes have made this transition at least three times, with the Sea Kraits, Laticaudinae, having split from terrestrial relatives in Asia about 16 million years ago, while at least two lineages within the Australian subfamily Hydrophiinae (together referred to as Sea Snakes) switched to a marine habit more recently. The three lineages show convergent evolution for a number of traits, including the development of laterally compressed bodies with paddle-like tails, the appearance of salt-excreting glands, and common life-history traits. A fourth group of (non-Elapid) Snakes, the Acrochordidae, are semi-aquatic, and often semi-marine in habit, and show some of these traits.

Marine Snakes typically produce fewer young than terrestrial Snakes, which has been linked to a need for gravid females to retain a hydrodynamic shape. Nevertheless, the offspring are typically larger at birth than those of their terrestrial relatives, which would seem to work against this.

In a paper published in the journal Royal Society Open Science on 13 December 2023, Richard Shine of the School of Natural Sciences at Macquarie University, Shai Meiri of the School of Zoology and Steinhardt Museum of Natural History at Tel-Aviv University, Terri Shine and Gregory Brown, also of the School of Natural Sciences at Macquarie University, and Claire Goiran of LabEx Corail and  Institut de sciences exactes et appliquées at the Université de la Nouvelle-Calédonie, examine the possibility that size-selective predation on young Snakes could be the driver of increased neonatal size in Marine Snakes.

Smaller terrestrial Snakes are known to be vulnerable to a wider range of predators than larger Snakes, with many predators targeting smaller Snakes while actively avoiding larger ones. However, predation rates on smaller Snakes can be lower than on larger individuals, due to the ability of small Snakes to remain inactive in well-hidden retreats.

Marine Snakes are less able to do this, as they must ascend to the surface to breath. This means that Snakes must leave their protective shelters and cross open water, where they are vulnerable to predation, several times per day. Predation of Snakes by large Fish during these crossings is well-documented, supporting the hypothesis that this is a risky endeavour for marine Snakes.

In order to test the hypothesis, Shine et al. first examined records of birth sizes in both marine and terrestrial Snakes, to confirm that the perceived trend was in fact real, then carried out experimental trials with model Snakes of different sizes to see if smaller Snakes were in fact more vulnerable to predation.

Shine et al. obtained data on hatchling and neonate sizes (Snakes can lay eggs or bear live young, but this does not appear to affect infant size much) and snout-vent lengths of adult females of 166 species of terrestrial, semi-aquatic, and marine Snakes, from published literature and the collection of the Steinhardt Museum. Semi-aquatic Snakes were found to produce slightly smaller offspring than terrestrial Snakes on average. However, the sample size for these Snakes was very small, and the subject was not investigated further. The adult snout-vent length for female Snakes in the study averaged at 800 mm, with the offspring of terrestrial Snakes having an average length of 200 mm, and the average length of new-born marine Snakes being 300 mm. 

Based upon this, Shine et al. hypothesised that a 200 mm Snake would be at significantly higher risk of predation in a typical marine Snake environment than a 300 mm Snake. To test this, an experiment was devised in which commercially available fibreglass fishing lures designed to resemble Snakes had their hooks removed and additional weights added to ensure they retained negative buoyancy, and were painted black to resemble the most common colour morph of the locally abundant Turtlehead Sea Snake, Emydocephalus  annulatus. These were then dragged by a snorkeler, Claire Goiran, over Coral reefs off the island of Ile aux Canards in New Caledonia, while a second snorkeler, Richard Shine, followed and recorded the reaction of large predatory Fish to the lures. 

A Camouflage Grouper, Epinephelus polyphekadion, following a black Snake-shaped lure, immediately prior to launching an attack. Teri Shine in Shine et al. (2023).

During 47 trials, Shine et al. recorded 114 responses. These included 38 attacks, and 76 encounters in which Fish followed the lure but did not attack. The size of the lure did not appear to influence whether or not Fish followed it, but they were significantly more likely to attack the smaller lures. Similarly, larger Fish were more likely to attack the lures, while smaller Fish tended to break off following without attacking. Thus, the majority of attacks were by large Fish on small lures.

Multiple lineages of Snakes which have invaded marine habitats have had an increase in neonatal size, combined with a reduced brood size (which are probably connected). Shine et al.'s study suggests that increased predation on smaller Snakes is a plausible explanation for this (although they stress that the results of their study cannot be taken as an absolute proof).

Shine et al. also note that larger Snakes are more likely to survive attacks by Fish, noting that two incidents of Snakes being seized by Fish and then released because the Fish was unable to overpower the Snake have been recorded on reefs close to their study area. In one of these incidents a Chocolate Grouper, Cephalopholis  boenak, unsuccessfully attacked a Turtlehead Sea Snake, Emydocephalus  annulatus, and in the other a Reef Stonefish, Synanceia verrucosa, was forced to break off an attack on a Blue Lipped Sea Krait, Laticauda  laticaudata, suggesting that larger size may present an advantage to young Snakes in surviving attacks, even if Fish do not discriminate against larger Snakes when choosing whether to attack.

A Reef Stonefish, Synanceia verrucosa, making an unsuccessful attack on a Blue Lipped Sea Krait, Laticauda  laticaudata, off the coast of Ile aux Canards in October 2022. Richard Fish/iNaturalist.

Predation is often cited as a likely cause of evolutionary pressure, influencing traits such as size and colouration. However, direct evidence of such impacts is difficult to gather accurate information on this unless predation rates are extremely high. Furthermore, it is difficult to design experiments looking at predatory behaviour for larger Animals without running into ethical and logistical constraints.

Predation is not the only driver of larger size in young marine Snakes which has been made, but it does seem to be the best supported by the available evidence. 

It has been suggested that larger size may provide an advantage when swimming, with smaller Snakes potentially being less efficient swimmers, using more energy to go slower. However, research into Sea Kraits has shown that smaller individuals have a higher swimming speed relative to crawling speed than larger individuals, suggesting that in these marine Snakes smaller size produces an advantage when swimming. 

Another possibility is that larger size in neonatal marine Snakes might be driven by prey size, with a shortage of suitable prey capturable by smaller Snakes creating a need for infant Snakes to be as large as possible. However, many Sea Snakes feed on smaller prey, notably members of the genus Emydocephalus are specialist feeders on Fish eggs, and several members of the genus Hydrophis have miniaturized heads and slender forebodies that enable them to penetrate the burrows of the small Fish upon which they prey.

Another possibility is that intraspecific competition drives larger size in young marine Snakes, with larger individuals excluding smaller individuals from better territories or access to prey. However, aggressive behaviour between members of the same species has never been observed in marine Snakes, making this unlikely.

Finally, larger size can act as a buffer against temperature changes, with larger bodies taking longer to either warm up or cool down that smaller bodies, thereby giving the Snakes more time to react to changes in conditions. However, marine environments offer much more protection against such temperature fluctuations than terrestrial ones, due to the high conductivity of water, making this highly unlikely as a driver of size in marine Snakes.

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Nemacheilus pullus: A new species of Stone Loach from central Laos.

Stone Loaches, Nemacheilidae, are freshwater Cypriniform Fish found throughout Eurasia, with one genus occurring in Ethiopia. They favour fast moving stretches of small streams, but are occasionally found in larger rivers, and even caves. The group currently contains about valid 790 species in 53 genera, with new species being described on a regular basis, particularly from Southeast Asia. The genus Nemacheilus currently includes 36 species from the Chao Phraya, Mae Khlong, and Mekong river drainages, the Malay Peninsula, and the islands of Sumatra, Java and Borneo. Members of this genus tend to be found in streams and rivers with slow to moderate flows and sand, gravel, or pebble bottoms.

In a paper published in the Raffles Bulletin of Zoology on 20 February 2023, Maurice Kottelat of the Lee KongChian Natural History Museum at the National University of Singapore, describes a new species of Nemacheilus from central Laos.

The new species is named Nemacheilus pullus, where 'pullus' is intended to mean dark yellow to blackish. The species is described from populations living in the Nam Ngiep and Nam Xan watersheds of the the Mekong drainage in central Laos, which were previously assigned to the species Nemacheilus platiceps.

Nemacheilus pullus, Laos: Mekong drainage: Nam Ngiep watershed; (a) CMK 27518, paratype, male, 37.7 mm; (b) MHNG 2787.091, holotype, male, 41.5 mm; (c) CMK 27518, paratype, female, 64.1 mm. Note that in b the specimen is slightly tilted laterally and the eye appears more distant from the dorsal profile than in reality. Kottelat (2023).

Nemacheilus pullus shares with Nemacheilus platiceps an incomplete lateral line, whereas in almost all other members of the genus the lateral line is complete. However Nemacheilus pullus lacks the clear flank bars of Nemacheilus platiceps, instead being a plain yellowish grey in colour (juveniles, and some adult females, do have faint bars, but these are much less clear than in Nemacheilus platiceps). 

Nemacheilus platiceps; (a) CMK 21392, 27.8 mm; Laos: Mekong drainage: Xe Kong watershed; (b)–(d) CMK 7927, Vietnam: Dong Nai drainage, 36.2 mm, (b) reversed) 40.8 mm, 54.4 mm, (d) reversed; and (e) NRM 15095, holotype, 40.1 mm; Vietnam Dong Nai drainage (reversed). Kottelat (2023).

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Sillago muktijoddhai & Sillago mengjialensis: Two new species of Sillago from Bangladesh.

Sillagos, Sillago spp., are inshore Perciform Fish widespread in the IndoPacific region. They form an important part of many food webs, feeding on Crustaceans and Molluscs in coastal waters or estuarine areas of rivers with open sandflats and muddy substrates, and in turn being fed upon by larger Fish, Marine Mammals, and Seabirds. Understanding the population structure of these Fish has proven difficult, as the genus contains a large number of very similar-appearing species, often identifiable only by the structure of their swim bladders, with the recent application of genetic profiling to the group suggesting that even this is not reliable, and that the group may contain more cryptic species (species which cannot easily be told apart by physical examination) than previously realised.

In a paper published in the journal Fishes on 18 April 2022, Shilpi Saha of the Fisheries College at the Ocean University of China, and the Department of Zoology at Jagannath University, Na Song and Zhengsen Yu, also of the Fisheries College at the Ocean University of China, Mohammad Abdul Baki, also of the Department of Zoology at Jagannath University, Roland McKay of the Chillagoe Museum, Jianguang Qin of the School of Biological Sciences at Flinders University, and Tianxiang Gao of the Fishery College at the Zhejiang Ocean University, describe two new species of Sillago from Bangladesh.

The new species are described from specimens obtained from fishermen at locations in Cox’s Bazar, Sundarbans, Patharghata, Maheshkhali and Saint Martin’s Island. These Fish are typically caught using beach seine nets in this area.

The first new species described is named Sillago muktijoddhai, were 'muktijoddhai' refers to the muktijoddha freedom fighters who fought for Bangladesh's independence from Pakistan from 1971 to 1979. 

Sillago muktijoddhai is elongated in shape, slightly steep anteriorly, and tubular posteriorly. The upper jaw is slightly protracted and crescentic, with minute villiform teeth on both jaws in one row. The back edge of the preopercle is slightly denticulated, and the opercle has one fragile spine posterodorsally. Gill rakers on the first arch are pointed and gradually become short towards the end. The body is covered with moderate-sized, overlapping ctenoid scales. The cheek scales cycloid, arranged in two rows.

There are two distinctly separate dorsal fins. The first dorsal fin is higher than the second, originating above the pectoral-fin base; its second spine is the longest, and the length of the succeeding spines decrease gradually. The base of the second dorsal fin is long, beginning at the midbody and not reaching the caudal-fin base when depressed. The anal fin originates slightly posterior to the anus, not reaching the caudal-fin base when depressed. The two disconnected pelvic fins are wide, roughly three-cornered, and shorter than the pectoral fin.

The body of Sillago muktijoddhai is greenish dorsally and light yellowish ventrally with black dots on the side below the lateral line. The cheek has black dots gathered on the anteroventral part of the eyes. The dorsal fins are hyaline, and small dark spots exist on the fin membrane, but those on the second dorsal fin form two or three distinct rows. The pectoral and pelvic fins are light yellowish. The anal fin is light yellowish with black spots. The caudal fin is light yellowish, dusky, and with a white edge; the lobes are truncated or emarginated.

Sillago muktijoddhai from the Bay of Bengal, Bangladesh. Saha et al. (2022).

The second new species is named Sillago mengjialensis, where 'mengjialensis' means 'from Mèngjiālā', where Mèngjiālā is the Chinese name for Bengal, in reference to the fact that the species was discovered as part of a collaborative project between scientists from China and Bangladesh.

The body of Sillago mengjialensis is elongated, somewhat conical anteriorly, and cylindric posteriorly. The back edge of the preopercle is slightly toothed. The opercle only has one weak spine posterodorsally. The gill rakers on the first arch are pointed and gradually become small towards the end. The body is covered with moderate-sized, overlapping ctenoid scales. The cheek scales are cycloid, arranged in two rows.

There are two disconnected dorsal fins. The first dorsal fin is higher than the second, originating above the pectoral fin base; its second spine is the longest, and the length of the succeeding spines decreases gradually. The base of the second dorsal fin is long, beginning at the midbody, and not reaching the caudal-fin base when depressed. The anal fin originates slightly posterior to the anus, not reaching the caudal-fin base when depressed. Two disconnected pelvic fins are large, roughly trigonal in shape, and smaller than the pectoral fin.

The body of Sillago mengjialensis is light olive greenish dorsally and silver ventrally with black spots on the sides below the lateral line. The cheek has black spots gathered on the anteroventral part of the eyes. The dorsal fins are hyaline with small dark spots on the fin membrane adjacent to the ray. The pectoral and pelvic fins are light yellowish. The anal fin is light yellowish to whitish with black dots. The caudal fin light yellowish, dusky, and has a white margin; the lobes are truncated or emarginated.

 

Sillago mengjialensis from the Bay of Bengal, Bangladesh. Saha et al. (2022).

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Neopagetopsis ionah: Vast nesting colony of Jonah's Icefish found in the Weddell Sea, Antarctica.

Crocodile Icefish, Channichtyidae, are highly specialised Perciform Fish found in the waters around Antarctica. They are sometimes known as White-blooded Icefish, as they lack haemoglobin; the cold waters around Antarctica being so saturated in oxygen that these Fish no not need a specialised means to transport it to their tissues (water is able to retain more free oxygen at lower temperatures). These Fish are known to nest in colonies, with a few tens of Fish typically building their nests together in a favoured spot.

In a paper published in the journal Current Biology on 13 January 2022, Autun Purser and Laura Hehemann of the Alfred Wegener Institute at the Helmholtz Centre for Polar and Marine Research, Lilian Boehringer, also of the Alfred Wegener Institute, and of Universität Bremen, Sandra Tippenhauer again of the Alfred Wegener Institute, Mia Wege of the Alfred Wegener Institute and the Mammal Research Institute at the University of Pretoria, Horst Bornemann, Santiago Pineda-Metz, Clara Flintrop, Florian Koch, and Hartmut Hellmer, again of the Alfred Wegener Institute, Patricia Burkhardt-Holm of the Programme Man-Society-Environment at the University of Basel, Markus Janout, again of the Alfred Wegener Institute, Ellen Werner of the HafenCity University Hamburg, Barbara Glemser of Universität Bremen and the Max Planck Institute for Marine Microbiology, Jenna Balaguer, also of the Alfred Wegener Institute, Andreas Rogge of the Alfred Wegener Institute and the Institute for Ecosystem Research at Kiel University, Moritz Holtappels, once again of the Alfred Wegener Institute, and Frank Wenzhoefer of the Alfred Wegener Institute, the Max Planck Institute for Marine Microbiology, and the Department of Biology at the University of Southern Denmark, describe a vast colony of Channichtyida Icefish numbering tens of thousands of nests, discovered on the eastern flank of the Filchner Trough within the Weddell Sea.

The colony is of Jonah's Icefish, Neopagetopsis ionah, a benthopelagic species (species that lives just above thes seafloor) known from the Weddell Sea, Kapp Norvegica, Halley Bay, Vahsel Bay, the Antarctic Peninsula, and the Ross Sea, with a pelagic juvenile stage (juvenile stage that lives in the water column), which has been reported from the Weddell Sea, South Shetland Islands, and McMurdo Sound. Purser et al. report a colony of about 16 160 Icefish covering an area of about 45 600 m², which was discovered by the Ocean Floor Observation and Bathymetry System, towed camera platform deployed by the RV Polarstern.

 

Seafloor images of the most expansive Icefish breeding colony discovered to date (A) Left: Neopagetopsis ionah in an active Fish nest on the eastern flank of the Filchner Trough, 497-m depth. Each
15-cm-deep nest has been shaped by removing the fine sediment and exposing numerous small stones, upon which the light blue eggs are laid. Right: dense array of active Fish nests. (B) Two Fish nests, spaced
15 cm from each other, imaged from the active nesting area of the Filchner Trough eastern flank. The left nest is in active use, whereas the right nest contains the remains of dead Fish only. [A] Surrounding seafloor with thin layer of phytodetritus visible. [B] Faint rim of very fine black rocky material marks the extreme extent of the active Fish nest. [C] A ring of uniform grey upper sediments cut through by the nest structure forms the upper sides of each active nest. [D] A ring of slightly coarser black rock fragments makes up the lower flanks of the active Fish nest. [E] The base of the active Fish nest is made up of numerous rock fragments from a range of lithologies, presumably carried to the area by ice rafting from a range of Antarctic source lithologies. [F] Neopagetopsis ionah eggs cover much of the rocky nest base layer. [G[ Adult Fish commonly observed centrally placed within the nest. [H[ Nest containing dead Fish in various states of decay. [I] Recently deceased Fish being fed on by a Starfish. [J] At least three additional adult Fish carcasses covered with Bacterial mat(s). [K] Numerous Ophiuroids in highest abundance within and surrounding nests containing dead Fish. [L] Small Fish, potentially a scavenger. [M] Pycnogonid of
20-cm diameter, commonly observed in the vicinity of active nests. In this image, several Neopagetopsis ionah eggs seem to be visible below the Pycnogonid. (C) Unused nest arrays on the Filchner Sill and elsewhere in the Filchner Trough. [1] Station 26_7; various sessile suspension feeders occupy the center of nests. [2] Station 30_7; small sessile fauna use small rocks within the unoccupied nest as a substrate on which to settle. [3] Station 54_1; some infilling of the center of the unused nest with sediment and hydrodynamically trapped detritus. [4] Station 72_8; softer sediments render the edges of the unused nests less distinct, though the central nest floor is abundant with larger stone fragments. Purser et al. (2022).

The deepest parts of the colony were at a depth of 535 m, the shallowest 420 m. Nests were of a fairly uniform size, about 75 cm wide and 15 cm deep, and were a minimum of 25 cm from their neighbours, even in the most densely populated parts of the colony. Of the total 16 160 nests directly imaged by camera, 12 020 (79%) were currently occupied (defined by the presence of either a Fish and eggs or just eggs). Another 15% of the nests were empty, 9% contained at least one dead Fish, and 2% contained Fish but not eggs.

The nests were bowl shaped and comprised a ring of stones, with a base of fine-grained material. The Icefish kept these areas free of any debris, as well as guarding the eggs against predators and fanning them to ensure a good supply of oxygen. The outer ring of stones may serve to prevent the eggs being blown away by this fanning action. 

In addition to the occupied area, further, more widely spaced nests could be observed in the area around the colony, all empty and all less than 100 m deeper than the deepest colony nests or less than 100 m shallower than the shallowest colony nests, though the edge of the colony is quite abrupt in both directions, suggesting that the edge of the environmentally suitable zone was also abrupt, but had moved in the past, presumably in response to climate variability.

Throughout the period of the study the seafloor temperature remained between -1.0°C and 0°C. This is typical of the modified Warm Deep Water current, which flows upward onto the Weddell Shelf, through the Filchner Trough and other similar troughs. These waters have an oxygen saturation of 65-75%, which is lower than the surrounding waters, which have an average oxygen saturation of 80%, and a temperature of -2.0°C to -1.5°C, supporting the idea that the eggs need very specific environmental conditions to survive.

Chlorophyll a levels and primary production appeared to be higher above the colony area, and areas with unoccupied nests, than the surrounding waters, with the highest concentrations of particles around the modified Warm Deep Water current-High-Salinity Shelf Water interface. The majority of these particles were below 300 μm in equivalent spherical diameter, with the density of particles increasing at night, which is probably indicative of zooplankton migrating into the photic zone to feed at night. This would suggest a potential food source, both for the nesting Icefish and for their larvae, known to migrate into overlying waters following hatching.

The benthic invertebrate community around the colony was both low density and low diversity; dominated by Brittle Stars and Star Fish, and with some conspicuously large Pycnogonids ('Sea Spiders'), which were often in excess of 15 cm in diameter, and were often seen near eggs or egg husks outside of Fish nests, potentially washed out by currents or Fish movements. This is a distinctive fauna, and suggests that the Icefish are modifying the environment sufficiently to shape the local invertebrate community.

The carcasses of the Icefish appeared to provide an important food source for invertebrates. As many as four dead Fish were seen in a single nest, which since no more than two live Fish were ever seen in association with a single nest, suggest that the dead Fish, which are close to neutrally bouyant, can accumulate within nests. Brittle Stars, Starfish, Octopus, and various Fish species opportunistically feeding were observed around dead Icefish. It is likely that the breeding season takes a high toll on Icefish, as several months of tending eggs is apparently exhausting.

The area around the colony is also known to be home to a group of Weddell Seals, Leptonychotes weddelli, some of which have been tracked by satellite for long periods of time. These Seals are known to dive deeply looking for food, and to take Jonah's Icefish, suggesting that the colony may be serving as a regular food source for them. Other Seal species, such as Elephant Seals, Mirounga leonina, have also been seen in the area.

Abandoned nests outside the colony also appeared to play a significant ecological role, being colonised by sessile organisms, such as tube dwelling Polychaetes, colonial bryozoans, and Sponges. These sites also appeared to be hydrodynamically trapping phytodetritus, which would make them an excellent site for sessile organisms.

Because these observations were based upon a single observing season, a number of important questions about the breeding behaviour of the Jonah's Icefish remain unanswered. It is unclear how often the Fish build new nests; do they reuse them each year, or construct new ones? Do the Fish remain with the eggs from when they are laid till when they hatch, or do they leave to forage? How do the predators of both the Fish and their eggs behave around the colony? How do the hatchling Fish behave when they emerge? How do the Fish behave during the mating and spawning seasons? To what extent is the colony a food source for Weddell Seals, and how do they exploit it? In order to address these problems two LED light-and-camera systems were positioned 3 m above the seafloor and left collecting data, with the plan being to return and collect them in 2023 or 2024.

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