Forster's Tern
Forster's TernForster's TernForster's Tern

Forster's Tern

Sterna forsteri

Least ConcernNear ThreatenedVulnerableEndangeredCritically Endangered
20–30% · Possible
overall probability at Ría Lagartos Biosphere Reserve
202 Verified records at Ría Lagartos Biosphere Reserve
February Best month highest sighting rate
☀️ Diurnal When it's active during daytime hours (6am–6pm)

Forster's tern (Sterna forsteri) is a tern in the family Laridae. The genus name Sterna is derived from Old English "stearn", "tern", and forsteri commemorates the naturalist Johann Reinhold Forster. It breeds inland in North America in the northern United States and southern Canada, and migrates south to winter in the southern United States, Mexico, the Caribbean, and northern Central America. It is also a rare but annual vagrant in western Europe, and has wintered in Ireland and Great Britain on a number of occasions. This species breeds in colonies in marshes. It nests in a ground scrape and lays two or more eggs. Wikipedia →

20–30% of wildlife watchers report a Forster's Tern sighting in Ría Lagartos Biosphere Reserve, based on 202 days of visitor records from GBIF citizen-science data.

Closest Relatives at Ría Lagartos Biosphere Reserve

Common Tern
LC

Common Tern

☀️ Diurnal Bird

Sterna hirundo

<5% · Rare
Laughing Gull
LC

Laughing Gull

☀️ Diurnal Bird

Leucophaeus atricilla

70–80% · Very likely
Royal Tern

Royal Tern

☀️ Diurnal Bird

Thalasseus maximus

60–70% · Likely
Sandwich Tern

Sandwich Tern

☀️ Diurnal Bird

Thalasseus sandvicensis

50–60% · Likely
Black Skimmer
LC

Black Skimmer

☀️ Diurnal Bird

Rynchops niger

40–50% · Likely
Gull-billed Tern

Gull-billed Tern

☀️ Diurnal Bird

Gelochelidon nilotica

20–30% · Possible
Caspian Tern
LC

Caspian Tern

☀️ Diurnal Bird

Hydroprogne caspia

20–30% · Possible
American Herring Gull
LC

American Herring Gull

☀️ Diurnal Bird

Larus smithsonianus

10–20% · With luck
Least Tern
LC

Least Tern

☀️ Diurnal Bird

Sternula antillarum

10–20% · With luck
Lesser Black-backed Gull
LC

Lesser Black-backed Gull

☀️ Diurnal Bird

Larus fuscus

10–20% · With luck
Ring-billed Gull
LC

Ring-billed Gull

☀️ Diurnal Bird

Larus delawarensis

5–10% · With luck
Cabot's Tern

Cabot's Tern

☀️ Diurnal Bird

Thalasseus acuflavidus

Insufficient data

📅 Monthly Probability

30–40
Jan
30–40
Feb
20–30
Mar
10–20
Apr
10–20
May
5–10
Jun
20–30
Jul
20–30
Aug
10–20
Sep
10–20
Oct
10–20
Nov
10–20
Dec

☀️ When They're Spotted

Most active during daytime hours (6am–6pm) · across all parks (global)

☀️Diurnal
☀️🌙🌙12am6am12pm6pm12am

Global Distribution

Where this species is recorded worldwide. Restricted to human observations from 2019 onwards — the same kind of record and the same period the probabilities on this page are built from, so collar-tracking studies, camera-trap arrays and museum specimens are excluded. Around Santa Rosa that removes 5,924 GPS fixes from a handful of tagged jaguars.

where this species is recorded (GBIF density — it tracks where observers go, not how likely a sighting is)  ·  parks where it occurs — tap a pin for the sighting probability there

Parks Where Found

# Park Country Probability
1 El Vizcaíno Biosphere Reserve 🇲🇽 Mexico
20–30%
2 Ría Lagartos Biosphere Reserve 🇲🇽 Mexico
20–30%
3 Channel Islands National Park 🇺🇸 United States
10–20%
4 Elk Island National Park 🇨🇦 Canada
10–20%
5 Riding Mountain National Park 🇨🇦 Canada
10–20%
6 Celestún Biosphere Reserve 🇲🇽 Mexico
5–10%
7 Ciénaga de Zapata 🇨🇺 Cuba
5–10%
8 Point Pelee National Park 🇨🇦 Canada
5–10%
9 Everglades National Park 🇺🇸 United States
<5%
10 Bahía de Loreto National Park 🇲🇽 Mexico
<5%
11 Big Cypress National Preserve 🇺🇸 United States
<5%
12 Sequoia and Kings Canyon National Parks 🇺🇸 United States
<5%
13 Grand Teton National Park 🇺🇸 United States
<5%
14 Yellowstone National Park 🇺🇸 United States
<5%
15 La Amistad International Park (Panama) 🇵🇦 Panama
<5%
16 Joshua Tree National Park 🇺🇸 United States
<5%
17 Arrecifes de Cozumel National Park 🇲🇽 Mexico
Insufficient data
18 Coiba National Park 🇵🇦 Panama
Insufficient data
19 Voyageurs National Park 🇺🇸 United States
Insufficient data
20 Redwood National Park 🇺🇸 United States
Insufficient data
21 Death Valley National Park 🇺🇸 United States
Insufficient data
22 Glacier National Park 🇺🇸 United States
Insufficient data
23 Rocky Mountain National Park 🇺🇸 United States
Insufficient data
24 Shenandoah National Park 🇺🇸 United States
Insufficient data

Quick answers

What are the chances of seeing a Forster's Tern in Ría Lagartos Biosphere Reserve?

About 21% of wildlife watchers report a Forster's Tern sighting in Ría Lagartos Biosphere Reserve, based on 202 days of visitor records from GBIF citizen-science data.

When is the best time to see Forster's Tern in Ría Lagartos Biosphere Reserve?

February has the highest sighting rate for Forster's Tern in Ría Lagartos Biosphere Reserve in our monthly data.

← Back to Ría Lagartos Biosphere Reserve