long-term bird banding stations or by long-term individual banders that could add to the incomplete data for hummingbirds. Long-term monitoring of bird-pollinated plants also could provide useful information on the stability of the ecosystem services they provide, particularly if plants pollinated solely by the birds are chosen.


Despite the paucity of long-term data, collectively there is reliable evidence that some North American pollinator species have become extinct or locally extirpated, or have exhibited decreases in population size (Table 2-6). At least two bumble bee species could face imminent extinction, and several other pollinators have declined significantly (honey bees and U.S. and Mexi-

TABLE 2-6 Illustrative Examples of Pollinators in North America for Which Evidence of Decline Is Available

Common Name

Species Name


Species for Which Quantitative Data Are Available




Honey bee

Apis mellifera

United States

Honey bee

A. mellifera


Franklin’s bumble bee

Bombus franklini

Pacific Northwest of the United States

Western bumble bee

B. occidentalis

Central California

Bumble bee

B. affinis

New York




Bay checkerspot butterfly

Euphydryas editha bayensis

Palo Alto, California and other localities




Long-nosed bat

Leptonycteris curasoae

United States and Mexico

Long-nosed bat

L. nivalis

United States and Mexico




Rufous hummingbird

Selasphorus rufus

United States and Canada

Allen’s hummingbird

S. sasin

United States

Species for Which Quantitative Data Are Not Available




Stingless bees

Melipona spp.

Southern Mexico


Trigona spp.


Pollen wasps

Pseudomasaris micheneri

Inyo County, California

Pollen wasps

P. macswaini





Hog-nosed bat

Choeronycteris mexicana


Banana bat

Musonycteris harrisoni


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