Northern Mockingbird Mimus polyglottos

1
Northern Mockingbird(Mimus polyglottos)

• Photo BBS
• Description
• Average length 10 inches7
• Average wingspan 14 inches7
• Average weight 1.7 ounces or 49 grams7
• Medium sized3
• Slender3
• Pale gray-brown above and whitish below
  (countershading)7
• Long tail1

• Kingdom Animalia9
• Phylum Chordata9
• Subphylum Vertebrata9
• Class Aves9
• Order Passiformes9
• Family Mimidae9
• Genus Mimus9
• Species Polyglottos9
• Subspecies Leucopterus and Poluglottos9
• Photo Cornell Lab of Ornithology
• General Characteristics

2
Habitat and Diet

• Habitat
• Towns.1
• Farms.1
• Roadsides.1
• Thickets.1
• Habitat generalist- thrive in suburban and
  natural habitats.6
• Thrives in suburban areas.4
• Benefited from farm abandonment because its a
  shrub-nesting bird.8

• Photo Cornell Lab of Ornithology

3
Vocalizations

• Song
• Primary song is learned.6
• Complex songs of warbles, squeaks, guttered
  notes, and melodious phrases that sometimes
  continue strongly for as long as 10-20 minutes.6
• Varied phrases in regimented series, each
  repeated 2-6 times with an obvious pause between
  series.7
• Sings from high perches.4
• Sings well into evening and begins again about an
  hour before dawn.6
• Northern Mockingbird Song http//faculty.maryville
  college.edu/crain/ornithology/BIO349a.htm
• Repertoire
• Open-ended learners.2
• Repertoires can exceed 150 songs.2
• Can add new sounds to complex repertoires as
  adults therefore, repertoire sizes may increase
  steadily with age.8
• Mimicry
• Mimics other birds songs.1
• Imitate other birds, frogs, insects, and car
  alarms.2
• Mimics squeaking fence gates or auto backfires.6
• Sometimes repeat songs learned from wintering
  groung.6
• May use other species songs to threaten them and
  defend the territory.8
• Call
• Harsh, dry chak.7

4
Reproduction

• Nest
• Nests in a small tree, shrub, vine tangle,
  thicket, or large cactus or exceptionally on a
  stump or fence post5
• Low nests (3-10 feet off ground)5
• Bulky cup of coarse dead twigs, sometimes thorny
  grasses, weed stems, decaying leaves, rags,
  string, cotton, etc.5
• Lined with fine grasses, rootlets, and sometimes
  hair or plant down5
• Built by both sexes5
• Males usually build many nests until the female
  selects one6
• Female usually finishes the lining of the nest6

• Breeding
• Most mimids in North America are monogamous, but
  few reports of polygany are seen in Northern
  Mockingbirds.6
• Breed first at one year old.6
• Breeds in open woodland, scattered trees, and
  bushes in more open country, and especially shade
  trees, shrubbery, and plantings around
  buildings.5
• Begins mid-February in the southwest and Florida
  to late April in the north.5
• Ends early September.5
• Usually has two or three broods.5
• Male takes over exclusive care of young
  fledglings when the female begins to construct
  new nest for 2nd clutch of eggs.8

5
Offspring

• Eggs
• Usually lay 3-5.5
• Subelliptical to elliptical.5
• Smooth.5
• Glossy.5
• Pale to greenish-blue, or with additional pinkish
  wash.5
• Speckled, spotted, and blotched with light red,
  chestnut-red, or reddish-brown and paler lilac.5
• Concentration of markings at larger end.5

• Incubation
• 11 to 14 days.5
• Eggs laid at daily interval.5
• Only female incubates.5
• Source Cornell Lab of Ornithology
• Nestlings
• Altricial- meaning that the fledglings require
  parental care, as opposed to precocial.5
• Downy.5
• Down is a pale gray.5
• Mouth is yellow.5
• Gape flanges are yellow.5

6
Behavior

• Territoriality
• Vigorously defends territory.4
• Defends berry-rich wintering area as much as
  breeding territory.8
• Has been seen mobbing a domesticated cat.8
• May use other species songs to threaten them and
  defend the territory.8
• Intraspecific Competition
• Fiercely defends fruit-laden shrub against other
  mockingbirds.8
• Courtship Displays
• Most mimids in North America are monogamous, but
  few reports of polygany are seen in Northern
  Mockingbirds.6
• Males take over exclusive care of young
  fledglings when the female begins to construct
  new nest for 2nd clutch of eggs.8
• Only female incubates.5
• One elaborate flight display occurs when the male
  jumps from his perch mid-song, flaps a few times
  until he is above where he started, then
  parachutes with his wings back to his perch.6
• Ritualized nesting or breeding activity carries
  and presents nest materials.8
• Males usually build many nests until the female
  selects one.6
• Foraging
• Feeds mainly on the ground, running or hopping
  short distances and sometimes lunging at prey.6
• Often jerkily raises wings while foraging,
  perhaps to startle insects.6

7
Distribution

• Ranges from northern U.S. to Mexico or Brazil4
• Recently expanded regions to the north due to
  suburbs expanding in northeast North America,
  which means an increase in winter birdfeeding and
  berry-producing shrubs6
• Ornithologist believe numbers have been
  decreasing for the past two decades6
• According to the Breeding Bird Survey
• In Tennessee, Northern Mockingbirds are
  decreasing by a rate of 0.4140. However, the
  p-value is 0.1860, so these findings are not
  statistically significant9
• In the United States, N. Mockingbirds are
  decreasing by a rate of 0.58, which is
  statistically significant because the p-value is
  0.000009
• In Walland, N. Mockingbirds are decreasing by a
  rate of 7.5 with a significant p-value of
  0.00001. This trend has been observed for 23
  years.9
• The average count of N. Mockingbirds in Walland
  is 8.61.9

• Source BBS

8
Related Species

• Most closely related to Starlings.6
• Gnatcatchers resemble tiny Northern
  Mockingbirds.6
• Very similar to Bendires Thrasher and Loggerhead
  Shrike.6
• Bahama Mockingbird has been spotted in Florida on
  rare occasions.6
• Family is Mimidae which includes mockingbirds,
  catbirds, thrashers, and tremblers.6
• In North America this family includes Gray
  Catbird, Sage Thrasher, Brown Thrasher,
  Long-billed Thrasher, Bendires Thrasher,
  Curve-billed Thrasher, California Thrasher,
  Crissal Thrasher, Le Contes Thrasher.5
• Mimidae have similar characteristics including
• Small to medium sized bird.5
• Most are various shades of gray and brown.6
• Short-rounded wings.6
• Long legs and long tails.6
• Well- known for vocal repertoires and mimicking
  ability.6
• Arboreal.5
• Partially terrestrial.5
• Eats mainly insects and fruits.5
• Young fed insects brought in parents bill.5
• Young are downy with yellow or orange-red mouth
  and whitish gape flanges.5
• Eggs are blue or whitish and usually marked with
  fine speckling or spots and blotches of
  reddish-brown.5
• Male and female build nest, incubate eggs, and
  rear young.5

9
References

• Peterson, R. T. 2002. Peterson Field Guide Birds
  of Eastern and Central North America. Roughton
  Mifflin Company Boston. Pp. 248.
• Gill, F.B. 2007. Ornithology.3rd ed. W.H Freeman
  and Company New York. Pp. 230, 237, 441.
• Northern Mockingbird. 2005. The Encyclopedia
  Britannica. 15th ed. Encyclopedia Britannica
  Inc. Chicago. 15 pp. 104.
• Mimidae. 2005. The Encyclopedia Britannica.
  15th ed. Encyclopedia Britannica Inc. Chicago.
  8 pp. 212.
• Harrison, C.J.O. Baicich, P.J. 2005. A Guide to
  the Nests, Eggs, and Nestlings of North American
  Birds. 2nd ed. Princeton University Press
  Princeton, NJ. Pp. 258-259.
• Sibley, D.A. 2001. The Sibley Guide to Bird Life
  and Behavior.1st ed. Knopf Publishing Group. Pp.
  71, 83, 453, 468-474.
• Sibley, D.A. 2000. The Sibley Guide to Birds. 1st
  ed. Knopf Publishing Group. Pp. 411.
• Cornell Lab of Ornithology. 2004. Handbook of
  Bird Biology. 1st ed. Princeton University
  Press Princeton, NJ. Pp. 634, 9112, 651,
  670, 781-82, 727, 788, 769, 814, 939.
• Gough, G.A., Sauer, J.R., Iliff, M. Patuxent Bird
  Identification Infocenter. 1998. Version 97.1.
  Patuxent Wildlife Research Center, Laurel, MD.
  http//www.mbr-pwrc.usgs.gov/id/framlst/
  infocenter.html