Bird Research News

Vol.2 No.12

Varied Tit

Yamagara (Jpn) Poecile varius

2005. 12.14.

Morphology and classification
Classification: Passeriformes Paridae
Total length: Ca. 14cm
Wing length: ♂ 75.33 ± 1.46mm (n = 31) ♀ 69.36 ± 2.24mm (31)
Tail length:♂ 54.54 ± 2.33mm (31)
♀ 50.05 ± 2.44mm (30)
Culmen length: ♂ 10.93 ± 0.89mm (31)
♀ 11.15 ± 0.76mm (31)Tarsus length: ♂ 19.12 ± 1.20mm (31)
♀ 18.82 ± 0.51mm (31)Weight:♂ 16.33 ± 1.07mm (31)
♀ 15.33 ± 0.60mm (30)
Total length after Yoshii (ed. 1988), the other measurements of the breeding period inthe Aburayama Citizen's Forest in Fukuoka City, Fukuoka Prefecture (mean ± SD) bythe authors. The sex was judged by DNA assessment..

Appearance:
Adult males and females are similar in plumage coloration. The
head is black with a fine cream streak
from the crown to the nape. The foreheadand cheek are creamy white. The wings
and tail are bluish gray. The throat andchest are black. The belly and back isorange brown. However, Varied Tits varyconsiderably in plumage coloration between the subspecies. More southern subspecies tend to be darker in plumage. Juveniles are drab in plumage color. They Photo 1. Varied Tit
are milk-white on the abdomen, cheek and[Hideo Tani]
forehead, and dark gray on the back.
Varied Tits utter a nasal call like "Nee, nee", "Tsweee", etc. Theirsong sounds like "Tsoo-tsoo-bee, tsoo-tsoo-bee" with the accent on
the third syllable. However, the vocalization varies considerablyfrom one subspecies to another.

Distribution and Habitat
Distribution:
Varied Tits are distributed in Taiwan and the southern part of theKorean Peninsula as well as throughout Japan.

Habitat:
They primarily occur in broad-leaved evergreen forests (laurelforests in particular) from hills to mountains, but also inhabit abroad-leaved deciduous forest and a mixed forest of conifers andbroad-leaves.

Life history234

5

6breeding season

7891011 12

non-breeding season

Breeding system:
Varied Tits are socially monogamous. They maintain the pair-bondthroughout the year, but frequently divorce and mate again. Whenthey breed more than once in a season, they sometimes changetheir partners.

Nest:
Varied Tits nest in a tree cavity, but do
not excavate their own nest hole and use
an existing tree cavity. They often use
artificial structures such as a nest box.
They pile up moss in the bottom of anest hole and lay fine plant fibers andfur for the inner cup. They sometimes
use synthetic fibers as an inner cup lining in suburban areas. There

Photo 2. Varied Tit nestlings in a nest box.

24
♪ http://www.bird-research.jp/1_shiryo/koe/yamagara_070327_kodaira_mju.mp3
Mutsuyuki Ueta

Egg:The typical egg is milk-white with reddish brown flecks, but somebirds lay eggs without flecks. According to the study conductedfrom 1998 to 2000 in Fukuoka City, southern Japan, the clutch
size was 3-8 eggs with a mode of 4 eggs. However, life history
characters, such as a clutch size are known to vary between populations or subspecies in Varied Tits.

Incubation and nestling periods and fledging rate:
The male does not incubate the eggs and feeds the female during
the incubation period. It is assumed that the female mostly broods
the nestlings as well right after hatching. The incubation period isabout two weeks. The nestlings fledge about 16 days after hatching. Both parent birds feed the nestlings. The feeding frequency isnot very high. The author's observation showed that the parents fed
the young every 15 minutes even when they were 7-10 days old. In
other words, a male or female parent feeds the nestlings every 30
minutes. The food consists primarily of the larvae and adults oflepidoptera, and the sexes are roughly equal in feeding contribution. The nestlings rarely die of starvation and the breeding success
was mostly determined by the predation of snakes, etc.

Topics of ecology, behavior and conservation● Subspeciation

Vocalization:1

was a nest whose inner cup was lined with wild boar's fur in thestudy site, but the nest stank of a beast and the inner cup seemeduncomfortable because the fur was bristly.

Varied Tits include nine subspecies (Poecile varius varius, P. v.
namiei, P. v. owstoni, P. v. orii, P. v. sunsunpi, P. v. yakushimensis, P. v. amamii, P. v. olivaceus, and P. v. castaneoventris). However, P. varius orii is assumed to be extinct. It is probably because
the range consists mostly of many islands and the species is sedentary that the species has diverged into so many subspecies in acomparatively limited range composed of the Japanese Islands, thesouthern part of the Korean Peninsula and Taiwan. As a matter offact, no different subspecies occur sympatrically in large islands,
such as the main islands of Japan, and therefore there is no doubtthat the geographical isolation is principally responsible for Varied
Tit subspeciation.
Varied Tit subspecies have a tendency to become darker in plumage coloration in southern areas. The subspecies distributed along
the Izu islands (P. v. varius, P. v. namiyei and P. v. owstoni) become darker in plumage color, and larger in body size and smaller
in clutch size in southern areas. It is still unknown, however, what
evolutionary mechanism or effect of population genetics has givenrise to geographic inclines of morphological and life-historicalcharacters.

● A result of introgression? Individual variation amongsubspecies P. v. namiyei
The author has studied the ecology of P. v. namiyei in Kozushimaof the Izu Islands since 2003. This subspecies is distributed only inToshima, Niijima and Kozushima of the Izu Islands, and sandwiched between P. v. varius distributed north of Oshima and P. v.
owstoni distributed south of Miyakejima Island. This subspecies issaid to bear intermediate characteristics in morphology and life
history between P. v. varius and P. v. owstoni, as if it reflects thegeographic distribution. That is the case, but no study of the ecological and evolutionary mechanisms has been carried out yet.
Among the results the author has found, it was especially interesting that P. v. namiyei varied in plumage coloration between individuals. The typical plumage color is intermediate between thoseof P. v. varius and P. v. owstoni. The cheek is usually dark brown♪ http://www.bird-research.jp/1_shiryo/koe/yamagara-C_060529_tanzawa_mju.mp3
Mutsuyuki Ueta

Bird Research News

Vol.2 No.12

2005. 12.14.

© Japan Bird Research Association
Sumiyoshi 1-29-9, Fuchu, Tokyo, Japan

バードリサーチ生態図鑑and the back is dark gray. However,
the individual variation in cheekcolor was very large in KozushimaIsland. (Photo 3). The cheek ranged
in color from creamy white as thatof P. v. varius to dark brown. But
no P. v. namiyei had a cheek as
dark as that of P. v. owstoni. P. v.
namiyei with a pale cheek is notP.v. varius that has come to Kozushima from the neighboring islands
because the pale birds are larger
than P. v. various and fall into thebody size range of P. v. namiyei(Fig. 1).
It must be because P. v. namiyei isgeographically sandwiched between
P. v. various and P. v. owstoni thatP. v. namiyei has these color variations in plumage. There are possible
explanations for this phenomenon.
(A) Hybridization between different
subspecies has frequently occurred
between Varied Tit subspecies in
Kozushima, or (B) the genetic introgression has taken place between
P. v. namiyei and P. v. varius and/or P. v. owstoni. Probably hybridization between different subspecies
has not frequently occurred because
the breeding of the typical P. v.
owstoni and P. v. varius has notbeen confirmed in Kozushima. On
the other hand, if P. v. varius and/orP. v. owstoni even infrequently
comes to Niijima or Kozushima andthey breed with P. v. namiyei, thenthe genes of both or one of these Photo 3. Plumage color variasubspecies will infiltrate into thetions of Poecile varius
namiyei.
population of P. v. namiyei. The
infiltrated genes will spread into the
population of P. v. namiyei through the breeding of this subspecies. This phenomenon is called introgressive hybridization andhas been reported from various animals. I suspect that this mechanism is partly responsible for the abundance of plumage color
variations in P. v. namiyei. (as of Dec. 2005).

natural wing length (mm) tarsus length (mm)weight (g)● Caching for the nestlings
Varied Tits are well-known for food caching behavior. When Varied Tits come to a bird feeder with sunflower seeds, they sometimes take the seed to a nearby branch and eat it there and sometimes fly away with the seed into a forest. When they take the seedinto the forest, they probably cache it there. It is known that birds
with a habit of caching food can clearly remember where they
have hidden their food. P. v. owstoni is assumed to have a more
retentive memory because it is reported that this subspecies fed
cached seeds to the nestlings the next spring (Higuchi 1977). In
Aburayama Citizen's Forest, Fukuoka Prefecture, southern Japan,
on the other hand, many sunflower seedlings come out along a trailin the forest in spring. These seedlings suggest that although Varied Tits had cached sunflower seeds, they forgot to eat them or did
not need to eat them because other food was in plentiful supply.
How heavily they depend on their cached food will be related tothe abundance and constancy of food supply. It may be interesting
to compare the relations between these habitat factors and foodcaching behavior as well as spatio-temporal memories in various
Varied Tit populations.

● Varied Tits as a trick artist
Some of the senior citizens may remember Varied Tits as a "birdthat draws a written fortune (Omikujihiki)". The artist Varied Titswould ring the bell of a little shrine, open the door, take a sacredfortune out of the shrine and then poke the string that bind therolled fortune to cut it open. Wild Varied Tits drag insects and nuts
out of secluded places, beat them open using their bill and feet andcarry them in the bill. Using their innate behavior, the trainers
probably conditioned them to take an appropriate action in an appropriate order. Since Varied Tits are inherently curious and tame,
it is easy to get them to take food from people, which probably
opened the door to a trick artist as well.

Literature
Higuchi H. 1977. Stored nuts Castanopsis cuspidata as a food resource of nestling
Varied Tits Parus varius. Tori 26:9-12.
Koyama S. 1999. Varied Tit's trick art: in the cultural history and aspect of behavioral science. Hosei University Publications Service, Tokyo. [J]The Ornithological Society of Japan. 2000. Check-list of Japanese Birds revised
Sixth edition. The Ornithological Society of Japan, Hokkaido. [J+E]
Yamaguchi N. 2005. Cheek-patch coloration varies greatly within a subspecies ofthe Varied Tit Parus varius. Ibis 147:836-840.
Yoshii T. (Chief ed.). 1988. Concise Dictionary of Bird Names. Sanseido, Tokyo.
[J]Languages of literature cited other than English: [J] in Japanese, [J+E] in Japanesewith English summary.

Author
Fellow at Life Sci. Sci. Dept.
Noriyuki YAMAGUCHI Postdoctoral
Rikkyo University (as of Dec. 2005)

A

B

CA

B

CA

B

CFig. 1. Comparison of male body sizes of Varied Tit subspecies. (A) Poecile varius namiyei (n = 24), (B) Birds with an especially white cheekcaptured in Kozushima (n = 6) and (C) P. v. varius (n = 31). (Box:mean and S.E., whisker: maximum and minimum). drawn after Yamaguchi (2005).

Eight years have already passed since I started to study Varied Tits. I
owe it all to Varied Tits that I have received a doctorate and am getting
along somehow as a research worker. The study of Varied Tits is becoming increasingly interesting in Kozushima Island, and I would liketo continue the study in the island in the future, but as a post-doctoral
fellow, it is quite uncertain where I
will be and what I will be doing thefollowing year. I hope I will betaking a nap peacefully in spring,Oh-no, I will be indulged in studying Varied Tits in Kozushima Island. noriyuki@nagasaki-u.ac.jp53