Gavia adamsii
Silhouette: Graham Montgomery · PhyloPic
In 3 days <5% in a week ~10%
The yellow-billed loon (Gavia adamsii), also known as the white-billed diver, is the largest member of the loon or diver family. Breeding adults have a black head, white underparts and a chequered black-and-white mantle. Non-breeding plumage is drabber with the chin and foreneck white. Its main distinguishing feature is the long straw-yellow bill, which, because the culmen is straight, appears slightly uptilted.
It breeds in the Arctic and winters mainly at sea along the coasts of the northern Pacific Ocean and northwestern Norway; it also sometimes overwinters on large inland lakes. It occasionally strays well south of its normal wintering range and has been recorded as a vagrant in more than 22 countries. This species, like all divers, is a specialist fish-eater, catching its prey underwater. Its call is an eerie wailing, lower-pitched than the common loon.
First described by English zoologist George Robert Gray in 1859 based on a specimen collected in Alaska, the yellow-billed loon is a monotypic species, with no subspecies despite its large Holarctic range. It is closely related to the common loon, which it strongly resembles in plumage and behaviour... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Great Bear Rainforest | 🇨🇦 Canada |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 2 | San Francisco | 🇺🇸 United States | |
| 3 | San Diego | 🇺🇸 United States | |
| 4 | Denver | 🇺🇸 United States | |
| 5 | Seattle | 🇺🇸 United States | |
| 6 | Portland | 🇺🇸 United States | |
| 7 | Vancouver | 🇨🇦 Canada | |
| 8 | Los Angeles | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Yellow-billed Loon sighting in San Diego on a given day, based on 610 verified sightings from GBIF citizen-science data. It is the 201st most-seen of the 386 birds we can rate there. Over three days the chance rises to under 5%, and over a week to about 10%, if each day is a fresh chance.
January
In that month about 10% of wildlife watchers report a Yellow-billed Loon in San Diego on a given day, against under 5% in February to December, the lowest months. That is one of San Diego's wettest months, with about 40 mm of rain against almost none in July.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Yellow-billed Loon sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 8 cities where we can rate Yellow-billed Loon sightings, San Diego ranks 3rd at under 5%, level with the leaders once rounded. The best odds are in Minneapolis [Saint Paul] (United States, under 5%) and San Francisco (United States, under 5%).
GBIF citizen-science records
It is estimated from how often the Yellow-billed Loon is recorded against all the birds logged in San Diego (610 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
