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Hawaiian Monk Seal

Neomonachus schauinslandi

Mammal · family Phocidae · order Carnivora

  1. G1
    Critically imperiled
  2. G2
    Imperiled
  3. G3
    Vulnerable
  4. G4
    Apparently secure
  5. G5
    Secure

NatureServe global rank G2: imperiled[2].

Updated October 30, 2026. Published by Humblebee.

Endangered Species Act
Endangered[1]
NatureServe global rank
G2 Imperiled[2]
Native in
1 state[3]
Typical length
85 in[4]

The Hawaiian monk seal is a mammal in the seal family, Phocidae[5]. It is listed as Endangered under the US Endangered Species Act and NatureServe records it as native in Hawaii[1][3].

Conservation status

The US Endangered Species Act lists the Hawaiian monk seal as Endangered, a listing made on December 23, 1976[1]. NatureServe ranks it G2 (Imperiled) worldwide and N2 (Imperiled) in the United States[2][6]. The IUCN Red List category recorded by NatureServe is Vulnerable[7]. CITES lists it in Appendix I, which sets controls on international trade[8]. NatureServe estimates the total adult population at 1000 to 2500 individuals[9].

Status Value
Endangered Species Act[1] Endangered, listed December 23, 1976
NatureServe global rank[2] G2 (Imperiled)
NatureServe US rank[6] N2 (Imperiled)
IUCN Red List (via NatureServe)[7] Vulnerable
CITES (international trade)[8] Appendix I
Total population (NatureServe estimate)[9] 1000 to 2500 individuals

Where Hawaiian Monk Seal lives

NatureServe lists the Hawaiian monk seal as native in one US state, Hawaii[3].

Alaska: not recordedAKMaine: not recordedMEWisconsin: not recordedWIVermont: not recordedVTNew Hampshire: not recordedNHWashington: not recordedWAIdaho: not recordedIDMontana: not recordedMTNorth Dakota: not recordedNDMinnesota: not recordedMNIllinois: not recordedILMichigan: not recordedMINew York: not recordedNYMassachusetts: not recordedMAOregon: not recordedORNevada: not recordedNVWyoming: not recordedWYSouth Dakota: not recordedSDIowa: not recordedIAIndiana: not recordedINOhio: not recordedOHPennsylvania: not recordedPANew Jersey: not recordedNJConnecticut: not recordedCTRhode Island: not recordedRICalifornia: not recordedCAUtah: not recordedUTColorado: not recordedCONebraska: not recordedNEMissouri: not recordedMOKentucky: not recordedKYWest Virginia: not recordedWVVirginia: not recordedVAMaryland: not recordedMDDelaware: not recordedDEArizona: not recordedAZNew Mexico: not recordedNMKansas: not recordedKSArkansas: not recordedARTennessee: not recordedTNNorth Carolina: not recordedNCSouth Carolina: not recordedSCDistrict of Columbia: not recordedDCOklahoma: not recordedOKLouisiana: not recordedLAMississippi: not recordedMSAlabama: not recordedALGeorgia: not recordedGAHawaii: native, state rank S2HITexas: not recordedTXFlorida: not recordedFLPuerto Rico: not recordedPR
State presence as recorded by NatureServe[10].
Show state ranks (1 states)
StateRankMeaning
HawaiiS2Imperiled

Habitat

NatureServe records these habitat types for the Hawaiian monk seal: sand and dune, tidal flat and shore, pelagic (open ocean), and near shore[11]. The notes say it lives mainly in waters around islands, and it can also travel long distances in the open sea[12]. It rests on sandy beaches and sometimes on rocky or gravel shores[12]. Mothers tend to give birth where the water next to the shore is very shallow and the ground is stable[12].

Habitat types recorded by NatureServe[11]

Size and diet

NatureServe records the adult diet as fish eating and invertebrate eating[13]. The seals feed on the sea floor and take a wide variety of fishes, cephalopods, and crustaceans[14]. They feed in shallow lagoons and in deeper water, down to at least 500 meters[14]. NatureServe records a typical length of 215 cm (85 in) and a typical adult weight of 170 kg (375 lb)[4][15]. The facts here do not give a lifespan.

Trait Value
Typical length[4] 215 cm (85 in)
Typical adult weight[15] 170 kg (375 lb)
Food habits[13] Piscivore, Invertivore

When to look for it

GBIF has observation records of the Hawaiian monk seal in every month of the year[16]. Most records fall in January, March and August[16]. These records show when people look and report, not how many animals there are[16].

January: 276 recordsJanFebruary: 267 recordsFebMarch: 282 recordsMarApril: 221 recordsAprMay: 241 recordsMayJune: 232 recordsJunJuly: 204 recordsJulAugust: 272 recordsAugSeptember: 145 recordsSepOctober: 142 recordsOctNovember: 175 recordsNovDecember: 250 recordsDec
US observation records on GBIF by month, all years. The three months with the most records are highlighted. Records show when people look and report, not how many animals there are[16].
Show records by month
MonthRecords
January276
February267
March282
April221
May241
June232
July204
August272
September145
October142
November175
December250

Where to see it

This species is protected or at risk, so we show its range only at the state level. We do not publish parks, nesting, spawning or wintering sites.

Questions people ask

Is the Hawaiian monk seal endangered?
Yes. The US Endangered Species Act lists it as Endangered, listed December 23, 1976[1]. NatureServe ranks it G2 (Imperiled) globally[2].
Where does the Hawaiian monk seal live?
NatureServe lists it as native in one US state, Hawaii[3]. It lives mainly in waters around islands and sometimes travels long distances in the open ocean[12].
What does the Hawaiian monk seal eat?
NatureServe records it as eating fish and invertebrates[13]. Its diet includes a wide variety of fishes, cephalopods, and crustaceans[14].
How big is a Hawaiian monk seal?
NatureServe records a typical length of 215 cm (85 in) and a typical adult weight of 170 kg (375 lb)[4][15].
How many Hawaiian monk seals are there?
NatureServe estimates the total adult population at 1000 to 2500 individuals[9].

Facts and sources

  1. Under the US Endangered Species Act, Hawaiian monk seal has the status Endangered, listed December 23, 1976 (USFWS ECOS). USFWS ECOS
  2. NatureServe global conservation status rank for Hawaiian Monk Seal: G2 (Imperiled). NatureServe Explorer
  3. NatureServe lists Hawaiian Monk Seal as native in 1 US state or territory: Hawaii. NatureServe Explorer
  4. Typical length recorded by NatureServe: 215 cm (85 in). NatureServe Explorer
  5. Hawaiian Monk Seal (Neomonachus schauinslandi) is a mammal in the family Phocidae, order Carnivora. NatureServe Explorer
  6. NatureServe national rank in the United States: N2 (Imperiled). NatureServe Explorer
  7. IUCN Red List category as recorded by NatureServe: Vulnerable. NatureServe Explorer
  8. CITES listing recorded by NatureServe: Appendix I (controls on international trade). NatureServe Explorer
  9. NatureServe estimate of total adult population (global, as a range): 1000 to 2500 individuals. NatureServe Explorer
  10. NatureServe state ranks for Hawaiian Monk Seal (map and table on this page). NatureServe Explorer
  11. Habitat types NatureServe records for Hawaiian Monk Seal: Sand/dune, Tidal flat/shore, Pelagic, Near shore. NatureServe Explorer
  12. NatureServe notes on habitat for Hawaiian Monk Seal. NatureServe Explorer
  13. Adult food habits recorded by NatureServe: Piscivore, Invertivore. NatureServe Explorer
  14. NatureServe notes on food for Hawaiian Monk Seal. NatureServe Explorer
  15. Typical adult weight recorded by NatureServe: 170 kg (375 lb). NatureServe Explorer
  16. GBIF observation records of Hawaiian Monk Seal in the US by month (chart on this page). GBIF

Status, range and habitat come from NatureServe Explorer (CC BY 4.0) and USFWS ECOS at the snapshot date. Listings change by federal rule. State lists are where NatureServe records the species, not a promise that you will see it there. Never name a place smaller than a state. GBIF and park records count observations and checklists. They show where and when people report the species, not how many animals live there.

NatureServe. 2026. NatureServe Explorer [web application]. NatureServe, Arlington, Virginia. Available https://explorer.natureserve.org. (Accessed: October 30, 2026). Licensed under CC BY 4.0; SpeciesFacts selected and summarized it.