Maryland mammals

Common Bottlenose Dolphin in Maryland

Tursiops truncatus

Native to Maryland S4 Apparently Secure in Maryland

Not listed as nonindigenous in Maryland by USGS NAS; native to its Maryland range.

IUCN Red List status

  1. LC
  2. NT
  3. VU
  4. EN
  5. CR
  6. EW
  7. EX

LC – Least Concern

Widespread and abundant; not at risk.

Common Bottlenose Dolphin (Tursiops truncatus)Delfín mular (Tursiops truncatus), isla de San Cristóbal, islas Galápagos, Ecuador, 2015-07-24, DD 86Common Bottlenose Dolphin (Tursiops truncatus)Two wild bottlenose dolphins breaching in unison over gray coastal waterWild bottlenose dolphin surfacing head-on, beak and dorsal fin above the water
Photo: NASA · Public domainCommon Bottlenose Dolphin (Tursiops truncatus)Photo: Diego Delso · CC BY-SA 4.0Delfín mular (Tursiops truncatus), isla de San Cristóbal, islas Galápagos, Ecuador, 2015-07-24, DD 86Photo: Jonathan Eisen · CC BY 4.0Common Bottlenose Dolphin (Tursiops truncatus)Photo: steve b · CC0Two wild bottlenose dolphins breaching in unison over gray coastal waterPhoto: Rolf Lawrenz · CC BY 4.0Wild bottlenose dolphin surfacing head-on, beak and dorsal fin above the water

Common Bottlenose Dolphin in Maryland, by the numbers

Occasional in Maryland 38th most recorded of 57 mammals logged in Maryland

29 occurrence records

Records from 2000–2026.

When to look for the Common Bottlenose Dolphin in Maryland

Most sightings fall in September.

29 Maryland occurrence records (iNaturalist and GBIF) by month of year, 2000–2026. Shows when the species is recorded, not a guarantee of presence. Based on a small number of dated records; the seasonal pattern may not be representative.

Monthly Maryland records (table)
MonthRecords
January2
February1
March0
April3
May3
June1
July2
August5
September12
October0
November0
December0

Monthly common bottlenose dolphin occurrence records (iNaturalist and GBIF) in Maryland, 2000–2026.

Seasonality

Year-round in Maryland, with recorded sightings peaking in September.

Occurrence map

Where Common Bottlenose Dolphin has been recorded in Maryland

29 records mapped · zoom and drag to explore

29 Maryland records mapped

Where it's recorded in Maryland

CountyRecords
Worcester County 18
Kent County 3
Other localities 8

The complete county distribution, spread across 2 Maryland counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Common bottlenose dolphin sightings in Maryland cluster on the Atlantic side. Worcester County, home to Assateague Island and the state’s ocean coast, holds 18 of the 29 records, and Kent County, far up the Chesapeake Bay, holds 3. Reports here reflect boat- and shore-based sightings rather than any dedicated marine survey effort.

With only 29 records since 2000, the seasonal picture is thin, though September stands out with 12 of them. NatureServe ranks the species S4, Apparently Secure, in Maryland waters.

Common Bottlenose Dolphin (Tursiops truncatus)
Full species profile Common Bottlenose Dolphin Tursiops truncatus Size 2–4 m6.6–13.1 ft Weight 150–650 kg330.7–1433 lb Lifespan 60 yr View the full profile

More mammals in Maryland in the atlas

Data & sources

The data and visualizations on this page draw on these open sources:

  • GBIFCC-BY 4.0occurrence records behind the range map, elevation, and record counts
  • iNaturalistCC0 / CC-BY / CC-BY-SAobservations, photos, and audio recordings
  • NatureServe ExplorerCC-BYthe state conservation rank
  • IUCN Red Listattributed factthe global conservation status
  • USGS NASpublic domainnative / introduced status
  • Natural Earthpublic domainthe relief basemap
  • USFSpublic domainnational-forest boundaries