This is the animal people come to South Padre Island and see. The Texas Tech NSRL account calls it
the most common cetacean along the Texas coast, especially common near the passes that connect bays
to the open Gulf — which is a precise description of Brazos Santiago Pass, the deep cut between
South Padre Island and Brazos Island where the jetties funnel water, bait and boats together.
Adults reach about 3.5 m; the animal is stout, short-beaked and grey, with a sloping forehead and a
lower jaw that projects past the upper.
Two different stocks, one place. NOAA Fisheries manages Gulf bottlenose dolphins as separate
stocks, and the water off South Padre Island is where two of them meet.
Inside the lagoon: NOAA recognises 32 bay, sound and estuary (BSE) stocks in the northern Gulf,
and the southernmost of them is named the Laguna Madre stock — which, as NOAA's 2025
photo-identification analysis spells out, means the Lower Laguna Madre. The Upper Laguna Madre
belongs to the Nueces Bay/Corpus Christi Bay stock. Dolphins seen from the Queen Isabella Causeway
or from a bay-side dock are Laguna Madre stock animals. What NOAA knows about them is genuinely
thin. The stock assessment report carries an abundance estimate of **80 animals with a coefficient
of variation of 1.57 — from a 1992 survey**, and because NOAA treats any estimate older than eight
years as unusable for management, the minimum population estimate and the Potential Biological
Removal are both formally listed as unknown and undetermined. NOAA classifies the Laguna Madre
stock as strategic, along with almost every other BSE stock, on the reasoning that the stocks are
of unknown but probably small size, so few deaths would be needed to exceed a sustainable removal
rate. Documented human-caused mortality and serious injury ran at a minimum of **0.8 animals a
year** across 2015–2019.
A newer figure exists but is not a population estimate. A NOAA Southeast Fisheries Science Center
analysis dated 29 April 2025 used photo-identification data gathered from April 2018 onwards
by Texas A&M University–Corpus Christi and the Texas Sealife Center to derive a **minimum count of
222 dolphins** for the Laguna Madre stock. The document is explicit that this undercounts: it omits
animals without distinctive dorsal fins, mostly calves, and any dolphin never photographed. Two
further findings matter. The Lower Laguna Madre is the least-surveyed of the three Texas bay
systems examined — 78 group sightings against 814 in Corpus Christi Bay. And the boundary leaks: of
dolphins first photographed in the Laguna Madre, only 65 per cent were finally assigned there
and 32.5 per cent to Corpus Christi Bay, which NOAA reads as evidence that either the boundaries
lack precision or these are not separate populations at all.
Outside the pass: dolphins in the surf, off the jetties and out over the shelf belong to the
Gulf of Mexico Western Coastal stock, defined as coastal water from the shore and barrier
islands out to the 20-metre depth contour, from the Mississippi River Delta to the Texas–Mexico
border. Here the numbers are firm: 20,759 animals (CV 0.13), from aerial surveys flown in
summer 2017 and autumn 2018, with a minimum population estimate of 18,585 and a Potential
Biological Removal of 167. This stock is not classified as strategic. The contrast is worth
holding in mind — some twenty thousand dolphins in the coastal strip, and a lagoon population that
NOAA cannot currently put a number on.
They move. The Western Coastal stock assessment cites a specific South Padre Island record: two
bottlenose dolphins previously photographed in the South Padre Island area were later identified in
Matagorda Bay, 285 km north, in May 1992 and May 1993.
What you will actually watch them doing. The behaviour most reliably seen here is feeding
association with shrimp boats: NSRL describes Texas bottlenose dolphins foraging around trawlers
whether working or not, taking fish drawn to the vessel and eating dumped bycatch. That habit has a
cost. NOAA records that between 1997 and 2019, 13 common bottlenose dolphins and nine
unidentified dolphins were entangled in lazy lines, turtle excluder devices or tickler chains on
observed Gulf shrimp trawl trips, and all but one died; a dolphin that stranded in 2015 had shrimp
trawl chaffing gear inside it, most likely swallowed while stripping gilled fish from the net. Mean
annual shrimp-trawl mortality for the Western Coastal stock over 2015–2019 was 32 animals.
Observe responsibly
Wildlife, tides and access conditions change. Keep a respectful distance, do not feed wildlife, stay out of dunes and marked nesting areas, and use current official rules before fishing or handling any catch.