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Grebes

Jessika Madison-Kennedy and Rebecca S. Duerr

Natural History

Grebes comprise 20 widely‐distributed species of waterbird that can be found on each continent
except Antarctica. They are the only members of the order Podicipediformes. The seven grebe spe-
cies found in North America are Black‐necked (or Eared), Clark’s, Horned, Least, Pied‐billed, Red‐
necked, and Western. The Western Grebe is best known for a display known as “rushing,” where
two birds race across the surface of the water in a graceful and coordinated courtship dance. Grebes
are migratory; however, some can be considered casual migrants and will move to large inland
bodies of water that remain open or will relocate to nearby coastal waters for the winter.
All grebes spend most of their time on the water, live as members of flocks, swim exclusively
with their feet, and have legs situated far back on their bodies. This adaption gives them excellent
swimming and diving capabilities, but makes walking on dry land challenging and unwieldy. Due
to the difficulty in maneuvering out of water and the inability to take off in flight from dry land,
grebes are often found grounded and are mistakenly thought to have broken legs by their finders.
Besides having unique leg positioning compared to other avian species, grebes can also be easily
identified by their distinctive feet, which have a laterally flattened tarsometatarsus and three large,
lobed toes that fold together to reduce water resistance on the upstroke, but open to become power-
ful and wide swimming paddles on the downstroke (Figure 10.1). Grebes have a feather structure
that allows them to adjust their buoyancy by trapping air against their body. By controlling the
amount of air trapped under the feathers, they are able to move above and below water with ease.
Grebes can catch small fish and invertebrates by diving or by slowly and stealthily submerging
themselves under the water.
Fish are the main food for most species of grebes. Grebes also eat a wide variety of aquatic inver-
tebrates including various insects, leeches, crayfish and other crustaceans, and snails and other
mollusks. Grebes will also eat frogs, tadpoles, and other small aquatic vertebrates. Natural diets vary
not only from species to species, but within the same species, based on what is available within a
specific habitat. Grebes are opportunistic and the body of water in which they live will largely dic-
tate their diet. For example, Pied‐billed Grebes in general favor fish such as carp, minnows, catfish,
sculpins, killifish, sticklebacks, gizzard shad, and sunfish; but those living in the fishless wetlands
of Manitoba primarily survive on a diet of tiger salamanders (Muller and Storer 1999).

Hand-Rearing Birds, Second Edition. Edited by Rebecca S. Duerr and Laurie J. Gage.
© 2020 John Wiley & Sons, Inc. Published 2020 by John Wiley & Sons, Inc.