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{{Use dmy dates|date=June 2021}}
{{Use dmy dates|date=June 2021}}
{{Speciesbox
{{Speciesbox
|name = Reedfish
| name = Reedfish
|image = Akwa19 reedfish.jpg
| image = Akwa19 reedfish.jpg
| image2 = Erpetoichthys calabaricus 01.jpg
|image_caption =
|status = NT
| status = NT
|status_system = IUCN3.1
| status_system = IUCN3.1
|status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=Lalèyè, P. |author2=Moelants, T. |author3=Olaosebikan, B.D. |date=2020 |title=''Erpetoichthys calabaricus'' |volume=2020 |page=e.T182479A135026602 |doi=10.2305/IUCN.UK.2020-2.RLTS.T182479A135026602.en |access-date=19 November 2021}}</ref>
| status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=Lalèyè, P. |author2=Moelants, T. |author3=Olaosebikan, B.D. |date=2020 |title=''Erpetoichthys calabaricus'' |volume=2020 |page=e.T182479A135026602 |doi=10.2305/IUCN.UK.2020-2.RLTS.T182479A135026602.en |access-date=19 November 2021}}</ref>
|genus = Erpetoichthys
| genus = Erpetoichthys
|parent_authority = [[John Alexander Smith (zoologist)|J. A. Smith]], 1865
| parent_authority = [[John Alexander Smith (zoologist)|J. A. Smith]], 1865
|species = calabaricus
| species = calabaricus
|authority = [[John Alexander Smith (zoologist)|J. A. Smith]], 1865
| authority = [[John Alexander Smith (zoologist)|J. A. Smith]], 1865
| range_map = Erpetoichthys calabaricus Map.jpg
|synonyms =
*''Calamoichthys calabaricus'' <small>(Smith 1865) Smith 1866</small>
| synonyms = *''Calamoichthys calabaricus'' <small>(Smith 1865) Smith 1866</small>
*''Erpetoichthys robbianus'' <small>Smith 1865</small>
*''Erpetoichthys robbianus'' <small>Smith 1865</small>
*''Polypterus erpetoideus'' <small>Smith 1865</small>
*''Polypterus erpetoideus'' <small>Smith 1865</small>
|synonyms_ref = <ref>{{cite web|last=Froese|first=R.|last2=Pauly|first2=D.|year=2017|title=Polypteridae |url=http://www.fishbase.se/Summary/FamilySummary.php?ID=31|website=[[FishBase]]|access-date=18 May 2017}}</ref><ref>{{cite web|title=Polypteridae|url=http://deeplyfish.com/wp-content/uploads/2017/05/Family-Polypteridae-PDF.pdf|website=Deeplyfish- fishes of the world|access-date=18 May 2017}}</ref>
| synonyms_ref = <ref>{{cite web|last=Froese|first=R.|last2=Pauly|first2=D.|year=2017|title=Polypteridae |url=http://www.fishbase.se/Summary/FamilySummary.php?ID=31|website=[[FishBase]]|access-date=18 May 2017}}</ref><ref>{{cite web|title=Polypteridae|url=http://deeplyfish.com/wp-content/uploads/2017/05/Family-Polypteridae-PDF.pdf|website=Deeplyfish- fishes of the world|access-date=18 May 2017}}</ref>
}}
}}


The '''reedfish''', '''ropefish''' (more commonly used in the United States), or '''snakefish''', ''Erpetoichthys calabaricus'', is a [[species]] of [[freshwater fish]] in the [[bichir]] [[family (biology)|family]] and [[order (biology)|order]]. It is the [[monotypic|only member]] of the [[genus]] '''''Erpetoichthys'''''. It is native to [[West Africa|West]] and [[Middle Africa|Central Africa]]. The reedfish possesses a pair of lungs in addition to gills, allowing it to survive in very oxygen-poor water. It is threatened by [[habitat loss]] through [[palm oil]] plantations, other agriculture, deforestation, and urban development.<ref name="iucn status 19 November 2021" />
The '''reedfish''', '''ropefish''' (more commonly used in the United States), or '''snakefish''', '''''Erpetoichthys calabaricus''''', is a [[species]] of fish in the [[family (biology)|family]] [[Polypteridae]] alongside the bichirs. It is the [[monotypic|only member]] of the [[genus]] '''''Erpetoichthys'''''. It is native to fresh and [[brackish]] waters in [[West Africa|West]] and [[Middle Africa|Central Africa]]. The reedfish possesses a pair of lungs in addition to gills, allowing it to survive in very oxygen-poor water. It is threatened by [[habitat loss]] through [[palm oil]] plantations, other agriculture, deforestation, and urban development.<ref name="iucn status 19 November 2021" />


==Description==
==Description==
The largest confirmed reedfish [[Zoological specimen|museum specimen]] was {{cvt|37|cm}} long,<ref name=fishbase/><ref name=PFK>{{cite web| title=A breeding first: The Reedfish | url=https://www.practicalfishkeeping.co.uk/features/a-breeding-first-the-reedfish/ | publisher=Practical Fishkeeping | access-date=16 June 2022 }}</ref> and studies where many hundred were caught and measured in the wild found none exceeding {{cvt|40|cm}}.<ref>{{cite journal| last=Ekpe | first=A.I. | last2=Asikpo | first2=E.-I. M. | year=2019 | title=Sex ratio, size structure and condition index in the rope fish, Erpetoichthys calabaricus (Polypteridae) from a Niger Delta flood plain, Nigeria | journal=International Journal of Fisheries and Aquatic Studies | volume=7 | issue=1 | pages=205-209 }}</ref><ref>{{cite journal| last=Amiekan | first=N.A. | last2=Udo | first2=M.T. | last3=Brownson | first3=I.I. | last4=Obot | first4=O.I. | last5=Ekpo | first5=I.E. | year=2020 | title=Population dynamics of Calabar snakefish (= reed fish), Erpetoichthys calabaricus. (Teleostei: Polypteridae) (Smith, 1866) at Ibikpe Creek in Uruan, Nigeria | journal=Journal of Wetlands and Waste Management | volume=4 | issue=1 | pages=66-77 }}</ref> Although sometimes claimed to reach up to {{cvt|90|cm|ft|0}} long,<ref>{{cite web| title=Erpetoichthys calabaricus | url=https://www.seriouslyfish.com/species/erpetoichthys-calabaricus/ | publisher=SeriouslyFish | access-date=16 June 2022 }}</ref><ref>{{cite web| title=Understanding the Reedfish | url=https://www.tfhmagazine.com/articles/freshwater/understanding-the-reedfish | publisher=TFH Magazine | access-date=16 June 2022 }}</ref> it is incorrect.<ref>{{cite journal| last=Moritz | first=T. | last2=Britz | first2=R. | year=2019 | title=Revision of the extant Polypteridae (Actinopterygii: Cladistia) | journal=Ichthyological Exploration of Freshwaters | doi=10.23788/IEF-1094 }}</ref>
The largest confirmed reedfish [[Zoological specimen|museum specimen]] was {{cvt|37|cm}} long,<ref name=fishbase>{{FishBase|genus=Erpetoichthys|species=calabaricus|year=2014|month=March}}</ref><ref name=PFK>{{cite web| title=A breeding first: The Reedfish | url=https://www.practicalfishkeeping.co.uk/features/a-breeding-first-the-reedfish/ | publisher=Practical Fishkeeping | access-date=16 June 2022 }}</ref> and three studies where more than 2,000 wild reedfish were caught (using [[Fishing basket|basket traps]], meaning that only individuals longer than {{cvt|15-20|cm|disp=sqbr|0}} were retained) found none that exceeded {{cvt|41.4|cm}}.<ref>{{cite journal| last=King | first=R.P. | year=1996 | title=Length-weight relationships of Nigerian freshwater fishes | journal=The WorldFish Center | volume=19 | issue=3 | pages=49-52 }}</ref><ref>{{cite journal| last=Ekpe | first=A.I. | last2=Asikpo | first2=E.-I. M. | year=2019 | title=Sex ratio, size structure and condition index in the rope fish, Erpetoichthys calabaricus (Polypteridae) from a Niger Delta flood plain, Nigeria | journal=International Journal of Fisheries and Aquatic Studies | volume=7 | issue=1 | pages=205-209 }}</ref><ref name=Amiekan2020>{{cite journal| last=Amiekan | first=N.A. | last2=Udo | first2=M.T. | last3=Brownson | first3=I.I. | last4=Obot | first4=O.I. | last5=Ekpo | first5=I.E. | year=2020 | title=Population dynamics of Calabar snakefish (= reed fish), Erpetoichthys calabaricus. (Teleostei: Polypteridae) (Smith, 1866) at Ibikpe Creek in Uruan, Nigeria | journal=Journal of Wetlands and Waste Management | volume=4 | issue=1 | pages=66-77 }}</ref> Although sometimes claimed to reach up to {{cvt|90|cm|ft|0}} long,<ref>{{cite web| title=Erpetoichthys calabaricus | url=https://www.seriouslyfish.com/species/erpetoichthys-calabaricus/ | publisher=SeriouslyFish | access-date=16 June 2022 }}</ref><ref name=TFH>{{cite web| title=Understanding the Reedfish | url=https://www.tfhmagazine.com/articles/freshwater/understanding-the-reedfish | publisher=TFH Magazine | access-date=16 June 2022 }}</ref> this is incorrect.<ref name=Moritz2019>{{cite journal| last=Moritz | first=T. | last2=Britz | first2=R. | year=2019 | title=Revision of the extant Polypteridae (Actinopterygii: Cladistia) | journal=Ichthyological Exploration of Freshwaters | doi=10.23788/IEF-1094 }}</ref>


The reedfish has an eel-like, elongated body without a trace of a ventral fin. The long dorsal fin consist of a series of well-separated spines, each supporting one or several articulated rays and a membrane. The reedfish possesses a pair of [[lung]]s, enabling it to breathe atmospheric air. This allows the species to survive in water with low [[Oxygen saturation|dissolved oxygen]] content and to survive for an intermediate amount of time out of water. Larvae have conspicuous external gills, making them resemble [[salamander]] larvae.<ref name=fishbase/>
Body elongation in fishes, such as eels, usually happens through the addition of caudal (tail) vertebrae, but in [[bichir]]s it has happened through the addition of precaudal vertebrae. Reedfish have evolved a more snakelike body by having twice as many precaudal vertebrae as the members of its sister genus [[Polypterus]], despite having the same number of tail vertebrae.<ref>[https://anatomypubs.onlinelibrary.wiley.com/doi/full/10.1002/ar.21491 Effects of Precaudal Elongation on Visceral Topography in a Basal Clade of Ray-Finned Fishes]</ref> [[Pelvic fin]]s are absent, and the long [[dorsal fin]] consist of a series of well-separated spines, each supporting one or several articulated rays and a membrane. The reedfish possesses a pair of [[lung]]s, enabling it to breathe atmospheric air. This allows the species to survive in water with low [[Oxygen saturation|dissolved oxygen]] content and to survive for an intermediate amount of time out of water.<ref name=fishbase/> The sexes are very similar in both median and maximum length, but females average heavier than males of a similar length, and they can be reliably separated by the shape of their [[anal fin]].<ref name=Moritz2019/><ref name=Asuquo2019>{{cite journal| last=Asuquo | first=I.E. | last2=Essien-Ibok | first2=M.A. | year=2019 | title=Sexual Dimorphism in Erpetoicthys calabaricus from a Mangrove Creek, Nigeria | journal=Asian Journal of Fisheries and Aquatic Research | volume=2 | issue=3 | pages=1-9 }}</ref> Reedfish are dark above and on the sides, with lighter orangish or yellowish underparts.<ref name=Moritz2019/> Males are generally more [[Olive (color)|olive]]-green in colour, whereas females generally are more yellowish-brown.<ref name=Asuquo2019/> [[Fish larvae|Larvae]] have conspicuous external gills, making them resemble [[salamander]] larvae.<ref name=fishbase/>


The [[genus]] name derives from the [[Ancient Greek language|Greek]] words ''erpeton'' (creeping thing) and ''ichthys'' (fish).<ref>{{cite book|first1=L.|last1=Fishelson|title=Zoology|year=1984|publisher=Hakibutz Hameuchad Publishing House|location=Israel|volume=2|pages=126}}</ref>
The [[genus]] name derives from the [[Ancient Greek language|Greek]] words ''erpeton'' (creeping thing) and ''ichthys'' (fish).<ref>{{cite book|first1=L.|last1=Fishelson|title=Zoology|year=1984|publisher=Hakibutz Hameuchad Publishing House|location=Israel|volume=2|pages=126}}</ref>


==Distribution and habitat==
==Distribution and habitat==
The reedfish inhabits slow-moving or standing, [[brackish]] or fresh, warm water at temperatures of {{convert|22|-|28|C|F|abbr=on}}. It occurs in [[Benin]], [[Cameroon]], [[Nigeria]] and possibly the [[Republic of the Congo]], spanning the area from the [[Ogun River]] to the [[Chiloango River]].<ref name=fishbase>{{FishBase|genus=Erpetoichthys|species=calabaricus|year=2014|month=March}}</ref>
The reedfish inhabits slow-moving or standing, fresh or [[brackish]], relatively warm tropical water, and usually in places with [[Reed (plant)|reeds]] or other dense plant growth. It occurs in [[Benin]], [[Cameroon]] and [[Nigeria]], spanning the area from the [[Ouémé River]] to the [[Sanaga River]].<ref name="iucn status 19 November 2021"/><ref name=Moritz2019/> There are old records from the [[Chiloango River]] in [[DR Congo]] and [[Cabinda Province|Cabinda]] in [[Angola]], but these are unconfirmed and questionable.<ref name="iucn status 19 November 2021"/><ref name=Moritz2019/>


==Ecology==
==Ecology==
The reedfish is [[nocturnal]], and feeds on [[annelid]] worms, [[crustacean]]s, and [[insect]]s.<ref name=fishbase/> When moving through water slowly, it tends to use its pectoral fins, changing to an eel-like form of swimming (making more use of full-body movements and the caudal fin) when moving quickly. Both in the wild and in captivity, reedfish are known to explore land if given the opportunity, slithering along like a snake and also taking food items on land.<ref name=locomotor>{{cite journal|title=Locomotor behavior across an environmental transition in the ropefish, Erpetoichthys calabaricus|journal=Journal of Experimental Biology|date=15 February 2011|issn=0022-0949|pmid=21270300|pages=530–537|volume=214|issue=4|doi=10.1242/jeb.047902|first=Cinnamon M.|last=Pace|first2=Alice C.|last2=Gibb|doi-access=free}}</ref>
The reedfish is [[nocturnal]], and feeds on [[annelid]] worms, small [[crustacean]]s (such as [[shrimp]]), [[insect]]s (both adults and their larvae), [[snail]]s and small fish.<ref name=fishbase/><ref name=TFH/><ref>{{cite web | last=Milner | first=J. | date=4 October 2021 | title=Rope Fish Profile: Care, Tanking and Feeding | url=https://theaquarium.club/rope-fish/ | publisher=The Aquarium Club | access-date=16 June 2022 }}</ref> When moving through water slowly, it tends to use its pectoral fins, changing to an eel-like form of swimming (making more use of full-body movements and the caudal fin) when moving quickly. Unlike their sister genus ''[[Polypterus]]'', which does not leave water voluntarily,<ref>{{cite journal | url=https://www.sciencedirect.com/science/article/abs/pii/S0944200616300265 | doi=10.1016/j.zool.2016.05.001 | pmid=27267147 | bibcode=2016Zool..119..447S | title=Locomotor flexibility of ''Polypterus senegalus'' across various aquatic and terrestrial substrates | last1=Standen | first1=Emily M. | last2=Du | first2=Trina Y. | last3=Laroche | first3=Philippe | last4=Larsson | first4=Hans C. E. | journal=Zoology | date=2016 | volume=119 | issue=5 | pages=447–454 }}</ref> reedfish are known to explore land both in the wild and in captivity if given the opportunity, slithering along like a snake and also taking food items on land.<ref name=locomotor>{{cite journal|title=Locomotor behavior across an environmental transition in the ropefish, ''Erpetoichthys calabaricus''|journal=Journal of Experimental Biology|date=15 February 2011|issn=0022-0949|pmid=21270300|pages=530–537|volume=214|issue=4|doi=10.1242/jeb.047902|first1=Cinnamon M.|last1=Pace|first2=Alice C.|last2=Gibb|doi-access=free}}</ref> Prey captured on land is brought back to the water.<ref>{{cite journal | doi=10.1002/ece3.2694 | title=Terrestrial capture of prey by the reedfish, a model species for stem tetrapods | date=2017 | last1=Van Wassenbergh | first1=Sam | last2=Bonte | first2=Christoffel | last3=Michel | first3=Krijn B. | journal=Ecology and Evolution | volume=7 | issue=11 | pages=3856–3860 | pmid=28616182 | pmc=5468123 | bibcode=2017EcoEv...7.3856V }}</ref>


Females repeatedly deposit small batches of eggs between the anal fins of the male, where they are fertilized. The male reedfish then scatters the eggs among aquatic vegetation, where they stick to plants and substrate. Larvae hatch rapidly (after 70 hours) but remain attached to vegetation; they become independent and start to feed after ~22 days, when the egg's [[yolk sac]] has been consumed.<ref name=fishbase/>
Females repeatedly deposit small batches of eggs between the anal fins of the male, where they are fertilized. The male reedfish then scatters the eggs among aquatic vegetation, where they stick to plants and substrate. Larvae hatch rapidly (after 70 hours) but remain attached to vegetation; they become independent and start to feed after ~22 days, when the egg's [[yolk sac]] has been consumed.<ref name=fishbase/>
[[Image:Erpetoichthys calabaricus.jpg|thumb|A yellowish-green ropefish amongst grey ''[[Polypterus senegalus]]'']]
[[File:Erpetoichthys calabaricus.jpg|thumb|A yellowish-green ropefish amongst grey ''[[Polypterus senegalus]]'']]


==Conservation==
==Conservation==
In coastal central Africa, the species is threatened by [[habitat loss]], driven by the development of oil palm plantations. Populations in western Africa are impacted by degradation and [[loss of habitat]] from wetland drainage for agricultural and urban developments. The reedfish is currently classified as [[Near Threatened]] by the [[International Union for Conservation of Nature|IUCN]].<ref name="iucn status 19 November 2021" />
In coastal central Africa, the species is threatened by [[habitat loss]], driven by the development of [[oil palm]] plantations. Populations in western Africa are impacted by degradation and loss of habitat from wetland drainage for agricultural and urban developments. The reedfish is currently classified as [[Near Threatened]] by the [[International Union for Conservation of Nature|IUCN]].<ref name="iucn status 19 November 2021" /> It is regarded as a good food fish and commonly caught in the local [[subsistence fishery]]. It is also regularly caught for the international aquarium fish trade. Overall, catch levels do not appear to represent a major threat to the species at present, but do need monitoring.<ref name=Amiekan2020/>


==In the aquarium==
==In the aquarium==
Reedfish are sometimes displayed in [[aquarium|aquaria]]. All aquarium fish are wild-caught; they have not yet been successfully bred in captivity. Spawning and hatching in captivity has been observed, but no hatchlings have been reported to survive to adulthood.<ref>[http://www.practicalfishkeeping.co.uk/features/articles/A%20breeding%20first:%20The%20Reedfish A breeding first: The Reedfish, Ralf Britz and Ritva Roesler, ''Practical Fishkeeping'', March 2009]</ref><ref>{{Cite web | url=https://www.fishkeeper.co.uk/databank/reed-fish-rope-fish | title=Reed Fish - Maidenhead Aquatics}}</ref>
Reedfish are sometimes displayed in [[aquarium|aquaria]]. All aquarium fish are wild-caught; they have not yet been successfully bred in captivity. Spawning and hatching in captivity has been observed, but no hatchlings have been reported to survive to adulthood.<ref name=PFK/><ref>{{Cite web | url=https://www.fishkeeper.co.uk/databank/reed-fish-rope-fish | title=Reed Fish - Maidenhead Aquatics}}</ref>


They are inquisitive, peaceful, and have some "personality". Although nocturnal, reedfish will sometimes come out during the day. Since they have a peaceful nature, other fish may "bully" a reedfish, despite its large size, especially in competition for food or space.<ref name=aqua-fish>[https://en.aqua-fish.net/fish/ropefish A profile of Ropefish] Retrieved 2 August 2017.</ref> Some reedfish also have an inclination to stay close to the water surface, where they will be safe from other fish and will even allow most of their bodies to leave the water at times.{{citation needed|date=April 2017}}
They are inquisitive, peaceful, and have some "personality". Although nocturnal, reedfish will sometimes come out during the day. Since they have a peaceful nature, other fish may "bully" a reedfish, despite its large size, especially in competition for food or space.<ref name=aqua-fish>[https://en.aqua-fish.net/fish/ropefish A profile of Ropefish] Retrieved 2 August 2017.</ref> Some reedfish also have an inclination to stay close to the water surface, where they will be safe from other fish and will even allow most of their bodies to leave the water at times.{{citation needed|date=April 2017}}

Latest revision as of 21:49, 21 September 2024

Reedfish
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Polypteriformes
Family: Polypteridae
Genus: Erpetoichthys
J. A. Smith, 1865
Species:
E. calabaricus
Binomial name
Erpetoichthys calabaricus
Synonyms[2][3]
  • Calamoichthys calabaricus (Smith 1865) Smith 1866
  • Erpetoichthys robbianus Smith 1865
  • Polypterus erpetoideus Smith 1865

The reedfish, ropefish (more commonly used in the United States), or snakefish, Erpetoichthys calabaricus, is a species of fish in the family Polypteridae alongside the bichirs. It is the only member of the genus Erpetoichthys. It is native to fresh and brackish waters in West and Central Africa. The reedfish possesses a pair of lungs in addition to gills, allowing it to survive in very oxygen-poor water. It is threatened by habitat loss through palm oil plantations, other agriculture, deforestation, and urban development.[1]

Description

[edit]

The largest confirmed reedfish museum specimen was 37 cm (15 in) long,[4][5] and three studies where more than 2,000 wild reedfish were caught (using basket traps, meaning that only individuals longer than 15–20 cm [6–8 in] were retained) found none that exceeded 41.4 cm (16.3 in).[6][7][8] Although sometimes claimed to reach up to 90 cm (3 ft) long,[9][10] this is incorrect.[11]

Body elongation in fishes, such as eels, usually happens through the addition of caudal (tail) vertebrae, but in bichirs it has happened through the addition of precaudal vertebrae. Reedfish have evolved a more snakelike body by having twice as many precaudal vertebrae as the members of its sister genus Polypterus, despite having the same number of tail vertebrae.[12] Pelvic fins are absent, and the long dorsal fin consist of a series of well-separated spines, each supporting one or several articulated rays and a membrane. The reedfish possesses a pair of lungs, enabling it to breathe atmospheric air. This allows the species to survive in water with low dissolved oxygen content and to survive for an intermediate amount of time out of water.[4] The sexes are very similar in both median and maximum length, but females average heavier than males of a similar length, and they can be reliably separated by the shape of their anal fin.[11][13] Reedfish are dark above and on the sides, with lighter orangish or yellowish underparts.[11] Males are generally more olive-green in colour, whereas females generally are more yellowish-brown.[13] Larvae have conspicuous external gills, making them resemble salamander larvae.[4]

The genus name derives from the Greek words erpeton (creeping thing) and ichthys (fish).[14]

Distribution and habitat

[edit]

The reedfish inhabits slow-moving or standing, fresh or brackish, relatively warm tropical water, and usually in places with reeds or other dense plant growth. It occurs in Benin, Cameroon and Nigeria, spanning the area from the Ouémé River to the Sanaga River.[1][11] There are old records from the Chiloango River in DR Congo and Cabinda in Angola, but these are unconfirmed and questionable.[1][11]

Ecology

[edit]

The reedfish is nocturnal, and feeds on annelid worms, small crustaceans (such as shrimp), insects (both adults and their larvae), snails and small fish.[4][10][15] When moving through water slowly, it tends to use its pectoral fins, changing to an eel-like form of swimming (making more use of full-body movements and the caudal fin) when moving quickly. Unlike their sister genus Polypterus, which does not leave water voluntarily,[16] reedfish are known to explore land both in the wild and in captivity if given the opportunity, slithering along like a snake and also taking food items on land.[17] Prey captured on land is brought back to the water.[18]

Females repeatedly deposit small batches of eggs between the anal fins of the male, where they are fertilized. The male reedfish then scatters the eggs among aquatic vegetation, where they stick to plants and substrate. Larvae hatch rapidly (after 70 hours) but remain attached to vegetation; they become independent and start to feed after ~22 days, when the egg's yolk sac has been consumed.[4]

A yellowish-green ropefish amongst grey Polypterus senegalus

Conservation

[edit]

In coastal central Africa, the species is threatened by habitat loss, driven by the development of oil palm plantations. Populations in western Africa are impacted by degradation and loss of habitat from wetland drainage for agricultural and urban developments. The reedfish is currently classified as Near Threatened by the IUCN.[1] It is regarded as a good food fish and commonly caught in the local subsistence fishery. It is also regularly caught for the international aquarium fish trade. Overall, catch levels do not appear to represent a major threat to the species at present, but do need monitoring.[8]

In the aquarium

[edit]

Reedfish are sometimes displayed in aquaria. All aquarium fish are wild-caught; they have not yet been successfully bred in captivity. Spawning and hatching in captivity has been observed, but no hatchlings have been reported to survive to adulthood.[5][19]

They are inquisitive, peaceful, and have some "personality". Although nocturnal, reedfish will sometimes come out during the day. Since they have a peaceful nature, other fish may "bully" a reedfish, despite its large size, especially in competition for food or space.[20] Some reedfish also have an inclination to stay close to the water surface, where they will be safe from other fish and will even allow most of their bodies to leave the water at times.[citation needed]

They can be difficult to keep; they will jump and enter pumps to escape tanks and frequently die as a result, and they can be sensitive to pH swings and nitrogen chemistry.[21][22][20] They will often consume other smaller fish when given the opportunity.[20] Often small feeder goldfish and minnows are eaten in place of bloodworms or nightcrawlers, and other commercially available live fish food.[citation needed]

See also

[edit]

References

[edit]
  1. ^ a b c d e Lalèyè, P.; Moelants, T.; Olaosebikan, B.D. (2020). "Erpetoichthys calabaricus". IUCN Red List of Threatened Species. 2020: e.T182479A135026602. doi:10.2305/IUCN.UK.2020-2.RLTS.T182479A135026602.en. Retrieved 19 November 2021.
  2. ^ Froese, R.; Pauly, D. (2017). "Polypteridae". FishBase. Retrieved 18 May 2017.
  3. ^ "Polypteridae" (PDF). Deeplyfish- fishes of the world. Retrieved 18 May 2017.
  4. ^ a b c d e Froese, Rainer; Pauly, Daniel (eds.). "Erpetoichthys calabaricus". FishBase. March 2014 version.
  5. ^ a b "A breeding first: The Reedfish". Practical Fishkeeping. Retrieved 16 June 2022.
  6. ^ King, R.P. (1996). "Length-weight relationships of Nigerian freshwater fishes". The WorldFish Center. 19 (3): 49–52.
  7. ^ Ekpe, A.I.; Asikpo, E.-I. M. (2019). "Sex ratio, size structure and condition index in the rope fish, Erpetoichthys calabaricus (Polypteridae) from a Niger Delta flood plain, Nigeria". International Journal of Fisheries and Aquatic Studies. 7 (1): 205–209.
  8. ^ a b Amiekan, N.A.; Udo, M.T.; Brownson, I.I.; Obot, O.I.; Ekpo, I.E. (2020). "Population dynamics of Calabar snakefish (= reed fish), Erpetoichthys calabaricus. (Teleostei: Polypteridae) (Smith, 1866) at Ibikpe Creek in Uruan, Nigeria". Journal of Wetlands and Waste Management. 4 (1): 66–77.
  9. ^ "Erpetoichthys calabaricus". SeriouslyFish. Retrieved 16 June 2022.
  10. ^ a b "Understanding the Reedfish". TFH Magazine. Retrieved 16 June 2022.
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