Wildlife
Ring of Fire
Watching an Island Grow
Dynamic
Bogoslof Island
Since the late 1700s an island cluster north of the
main arc of the Aleutian Islands has explosively grown, disappeared, reappeared,
and changed shapes. As recently as 1992 steam and ash plumes rose several miles
above Bogoslof Island. A new lava dome, about 150 m high, appeared on the north
tip of the island near the remnant of a dome created in 1927.
Volcanic
Home for Marine Animals
The islands are the emergent tips of an active
submarine volcano rising more than 4,500 feet (1,500 m) from the floor of the
Bering Sea. They are home to marine birds and mammals and part of the Alaska Maritime
National Wildlife Refuge.
TRACING BOGOSLOF'S VOLCANIC ACTIVITY
First Reports
In 1768 Russian sailors reported a small, rocky
prominence - called Ship Rock - was present in the area where Bogoslof and Fire
islands now rise. An explosive eruption began in 1796.
EYE
WITNESS ACCOUNT - Thunder and earthquakes rock the islands of Umnak and
Unalaska in the eastern Aleutian Islands. A glowing ash cloud obscures the horizon
toward an important fur seal and sea lion hunting island. When the cloud clears,
local Natives and Russian-American Company personnel see a huge island "shaped
like a black pointed cap." Twice the volcano hurls rocks as far as Umnak
– 30 miles. The island continues to grow. In 1804 when sea lion hunters visit
Agashagok (Aleut/Unangan) or Bogoslof Island, they find the water warm and the
ground still too hot for walking.
Changing Island
Profile
1768 Ship Rock present in general area.
1796 Eruptions
begin building a second island, south of Ship Rock
1804 Island formed;
called Bogoslof / Old Bogoslof /or Castle Rock
1823 Bogoslof stops
increasing in size
1882 Fire Island rises steaming, north of Ship
Rock
1890 Ship Rock has fallen
1906-10 Several eruptions
form and destroy new peaks
1922 Only Fire Island and Bogoslof remain,
separated by open water
1926-27 Kenyon Dome forms, surrounded by
a warm saltwater lagoon
Fire Island and Bogoslof are joined as one island again
1935 Open
water separates Bogoslof and Fire islands again
1947 Size of Fire
and Bogoslof islands greatly reduced since 1935
1953 Bogoslof further
reduced by about 25% since 1947
Saltwater lagoon now small pond
1973 Bogoslof
reduced by about 30% since 1953
Saltwater pond gone
1992 steam
and ash rise above island, new lava dome formed
LINKS to learn more
Bogoslof
in the Volcano Atlas
Wildlife responds to
changes on Bogoslof Island
Last updated:September 8, 2008
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