Aetomylaeus maculatus 

Scope: Global
Language: English

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Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Chondrichthyes Myliobatiformes Myliobatidae

Scientific Name: Aetomylaeus maculatus (Gray, 1834)
Common Name(s):
English Mottled Eagle Ray
Myliobatus maculatus Gray, 1834
Taxonomic Source(s): Weigmann, S. 2016. Annotated checklist of the living sharks, batoids and chimaeras (Chondrichthyes) of the world, with a focus on biogeographical diversity. Journal of Fish Biology 88(3): 837-1037.
Taxonomic Notes: Aetomylaeus milvus (Valenciennes in Müller & Henle, 1841) is most likely a synonym of this species. Further investigation is required.

Assessment Information [top]

Red List Category & Criteria: Endangered A2d+3d+4d ver 3.1
Year Published: 2006
Date Assessed: 2006-01-31
Needs updating
Assessor(s): White, W.T.
Reviewer(s): Kyne, P.M., Fowler, S.L. & Compagno, L.J.V. (Shark Red List Authority)
Aetomylaeus maculates is a medium-sized (to 78 cm disc width), inshore Indo-West Pacific eagle ray which is highly susceptible to a variety of fishing methods in regions where the level of exploitation of marine resources is extremely high (e.g., India, Thailand, Taiwan and Indonesia). It is caught regularly by demersal gillnet and trawl net fisheries that operate throughout its range. It is suspected to have limiting life history parameters similar to other myliobatid rays (including low fecundity). This species is assessed as Endangered under the criteria of A2bd+3d+4d due to the very high (and increasing) level of fishing pressure in inshore regions where it occurs, which is of great concern for any inshore species with limiting life history characteristics that is highly susceptible to fishing activities, and evidence of extirpation from some areas (this species no longer occurs in the Gulf of Thailand where eagle rays were historically common).

Geographic Range [top]

Range Description:Sporadic distribution in the Eastern Indian, Western Central Pacific and Northwest Pacific.
Countries occurrence:
China; India; Indonesia (Jawa, Kalimantan); Malaysia; Singapore; Sri Lanka; Taiwan, Province of China; Thailand
FAO Marine Fishing Areas:
Indian Ocean – eastern; Pacific – northwest; Pacific – western central
Additional data:
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:Appears to be naturally uncommon, observed in low numbers in fish markets in SE Asia.
Current Population Trend:Decreasing
Additional data:

Habitat and Ecology [top]

Habitat and Ecology:A little known species. Occurs on the inner continental shelf to depths of about 60 m over soft sandy substrate (Compagno and Last 1999). Reproductive biology, age and growth and dietary compositions are unknown for this species. Suspected low fecundity as with other myliobatids, for example Aetobatus narinari and Aetomylaeus nichofii, which bear litters of up to four offspring (Last and Stevens 1994, Compagno and Last 1999).

Life history parameters
Age at maturity (years): Unknown.
Size at maturity (disc width): Unknown (female); 55 cm DW not yet mature (mature by 71 cm DW) (W. White, unpubl. data) (male).
Longevity (years): Unknown.
Maximum size (disc width): 78 cm DW (Compagno and Last 1999).
Size at birth (cm): Unknown.
Average reproductive age (years): Unknown.
Gestation time (months): Unknown.
Reproductive periodicity: Unknown.
Average annual fecundity or litter size: Up to 4 (based in similar species).
Annual rate of population increase: Unknown.
Natural mortality: Unknown.

Threats [top]

Major Threat(s): Highly susceptible to a variety of inshore demersal fisheries, including trawls, gillnets and trammel nets which operate intensively throughout its range (e.g., India, Thailand, Taiwan and Indonesia). All caught are retained in most areas. Local eagle ray species are marketed in considerable numbers in Thailand and Malaysia (Compagno and Last 1999) and A. maculates is regularly landed in low numbers in the fish markets of Jakarta (Indonesia) by trawlers (W. White, unpublished data). Even though once common, eagle rays are now rare in the Gulf of Thailand (Compagno and Last 1999), where A. maculates has been locally extirpated (L.J.V. Compagno pers. comm.). Intensive demersal fisheries occur in India, in the species' known distribution (Hanfee 1999). There is very high level of exploitation on the habitat that this species occurs in throughout its entire range.

Conservation Actions [top]

Conservation Actions: None in place. Market surveys are currently being conducted for elasmobranchs in Indonesia.

The development and implementation of management plans (national and/or regional e.g., under the FAO International Plan of Action for the Conservation and Management of Sharks: IPOA-Sharks) are required to facilitate the conservation and sustainable management of all chondrichthyan species in the region. See Anon. (2004) for an update of progress made by nations in the range of A. maculates.

Classifications [top]

9. Marine Neritic -> 9.1. Marine Neritic - Pelagic
9. Marine Neritic -> 9.9. Marine Neritic - Seagrass (Submerged)
9. Marine Neritic -> 9.10. Marine Neritic - Estuaries
10. Marine Oceanic -> 10.1. Marine Oceanic - Epipelagic (0-200m)

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
In-Place Species Management
In-Place Education
5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> 5.4.3. Unintentional effects: (subsistence/small scale) [harvest]
♦ timing:Ongoing ♦ scope:Unknown ♦ severity:Unknown ⇒ Impact score:Unknown 
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> 5.4.4. Unintentional effects: (large scale) [harvest]
♦ timing:Ongoing ♦ scope:Unknown ♦ severity:Unknown ⇒ Impact score:Unknown 
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

0. Root -> 100.1. OLD 1.1.1-Policy-base actions->Management plans->Development
1. Research -> 1.1. Taxonomy
1. Research -> 1.2. Population size, distribution & trends
1. Research -> 1.3. Life history & ecology
1. Research -> 1.5. Threats
1. Research -> 1.6. Actions
3. Monitoring -> 3.1. Population trends

Bibliography [top]

Anonymous. 2004. Report on the implementation of the UN FAO International Plan of Action for Sharks (IPOA–Sharks). AC20 Inf. 5. Twentieth meeting of the CITES Animals Committee, Johannesburg (South Africa), 29 March–2 April 2004.

Compagno, L.J.V. and Last, P.R. 1999. Myliobatidae. Eagle rays. In: K.E. Carpenter and V.H. Niem (eds) FAO Species Identification Guide for Fishery Purposes. The Living Marine Resources of the Western Central Pacific. Volume 3. Batoid Fishes, Chimaeras and Bony Fishes Part 1 (Elopidae to Linophrynidae). pp. 1511-1519. Food and Agriculture Organization of the United Nations, Rome.

Hanfee, F. 1999. Management of shark fisheries in two Indian coastal states: Tamil Nadu and Kerala. In: R. Shotton (ed.) Case studies of the management of elasmobranch fisheries. FAO technical paper 378/1, FAO Rome.

IUCN. 2006. IUCN Red List of Threatened Species.

IUCN SSC Shark Specialist Group. Specialist Group website. Available at:

Last, P.R. and Stevens, J.D. 2009. Sharks and Rays of Australia. Second Edition. CSIRO Publishing, Collingwood.

Citation: White, W.T. 2006. Aetomylaeus maculatus. The IUCN Red List of Threatened Species 2006: e.T60120A12307534. . Downloaded on 22 September 2018.
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