Most of the land in the preserve is tundra, underlain by permafrost.
The tundra supports a variety of low and slow-growing plants.
The landscape is dominated by grasses and sedges, such as cottongrass.
Large trees cannot survive on the tundra.
Tree species are limited to dwarf species like Arctic willow, Alaska willow and dwarf birch.
Berry-bearing plants in the preserve include bog blueberry, crowberry, low-bush cranberry and cloudberry or salmonberry.
Lichens are found in rocky areas, including Cetraria, Cladina, Cladonia, Xanthoria and Umbilicaria genera.
Mosses and liverworts in the preserve include Sphagnum peat mosses, Aulacomnium bog mosses, Dicranum forked mosses, Polytrichum haircap mosses and Rhizomnium.
In spring the preserve features a variety of wildflowers, including Alpine Arnica, fireweed, Kamchatka rhododendron, Labrador tea, monkshood, one-flowered cinquefoil, harebell and alpine forget-me-not.

Caribou are survivors of the ice age environment in the preserve, together with reintroduced muskoxen.
The muskoxen were reintroduced to the area in 1970, after being wiped out in the early 20th century.
In addition to the native caribou, Siberian tundra reindeer (Rangifer tarandus sibiricus) were introduced in 1894, reaching a peak population of 600,000 animals in the 1930s.
The herd has since been reduced to about 4,000.
The Reindeer Act of 1937 prohibited ownership by non-Native Americans, and the reduced herds were managed by natives from that time onward.
Other mammals in the preserve are walruses, polar bears, red foxes, brown bears, Arctic foxes, ribbon seals, wolverines and beavers.
Significant nesting bird species include sandhill cranes and yellow-billed loons.

The Seward Peninsula's rivers and streams are habitat for freshwater fish and for anadromous salmon species.
The principal salmon species are chinook, coho, sockeye, chum and pink salmon.
Other salmonids such as Dolly Varden trout and Arctic grayling remain in freshwater throughout their life cycle.
The preserve also harbors northern pike and other fish.

The preserve has weather typical of northwestern Alaska, with long cold winters.
Weather is moderated by the coastal location, but temperatures can reach −65 °F (−54 °C) in winter and typical low temperatures in winter are −10 °F (−23 °C) to −20 °F (−29 °C).
Summer temperatures average about 50 °F (10 °C).
The average annual temperature is 21 °F (−6 °C).
Most of the land in the preserve is tundra, underlain by permafrost. The tundra supports a variety of low and slow-growing plants. The landscape is dominated by grasses and sedges, such as cottongrass. Large trees cannot survive on the tundra. Tree species are limited to dwarf species like Arctic willow, Alaska willow and dwarf birch. Berry-bearing plants in the preserve include bog blueberry, crowberry, low-bush cranberry and cloudberry or salmonberry. Lichens are found in rocky areas, including Cetraria, Cladina, Cladonia, Xanthoria and Umbilicaria genera. Mosses and liverworts in the preserve include Sphagnum peat mosses, Aulacomnium bog mosses, Dicranum forked mosses, Polytrichum haircap mosses and Rhizomnium. In spring the preserve features a variety of wildflowers, including Alpine Arnica, fireweed, Kamchatka rhododendron, Labrador tea, monkshood, one-flowered cinquefoil, harebell and alpine forget-me-not.
Caribou are survivors of the ice age environment in the preserve, together with reintroduced muskoxen. The muskoxen were reintroduced to the area in 1970, after being wiped out in the early 20th century. In addition to the native caribou, Siberian tundra reindeer (Rangifer tarandus sibiricus) were introduced in 1894, reaching a peak population of 600,000 animals in the 1930s. The herd has since been reduced to about 4,000. The Reindeer Act of 1937 prohibited ownership by non-Native Americans, and the reduced herds were managed by natives from that time onward. Other mammals in the preserve are walruses, polar bears, red foxes, brown bears, Arctic foxes, ribbon seals, wolverines and beavers. Significant nesting bird species include sandhill cranes and yellow-billed loons.
The Seward Peninsula's rivers and streams are habitat for freshwater fish and for anadromous salmon species. The principal salmon species are chinook, coho, sockeye, chum and pink salmon. Other salmonids such as Dolly Varden trout and Arctic grayling remain in freshwater throughout their life cycle. The preserve also harbors northern pike and other fish.
The preserve has weather typical of northwestern Alaska, with long cold winters. Weather is moderated by the coastal location, but temperatures can reach −65 °F (−54 °C) in winter and typical low temperatures in winter are −10 °F (−23 °C) to −20 °F (−29 °C). Summer temperatures average about 50 °F (10 °C). The average annual temperature is 21 °F (−6 °C).
Bering Land Bridge National Preserve