Tuesday, 14 February 2012
Marsh Tit
Scientific Name:
Poecile palustris
Length:
12 cm
Wingspan (mm):
18-19 cm
Weight:
10-12 g
Lifespan:
Up to 11 years, commonly 1-5 years. Description
Smaller than a great tit, slightly larger than a Coal Tit, similar in size to a Blue Tit and Willow Tit.
Separated from Coal Tit by lack of white wing bars, and lack of white nape. Coal Tit has larger bib and is noticeably smaller.
Very similar to Willow Tit. Best separated by cheek pattern and, if you can see it clearly, the bill. Marsh Tit has a pale mark at the base of the upper mandible, below the nostril. Willow Tit lacks this and has a shiny all-black bill. Marsh Tit usually shows whitish cheeks that contrast with a cold-grey brown wash behind the ear, towards the rear of the cheek patch. Willow Tit generally lacks contrast in the cheek patch, but may show a warm buff tinge towards the neck.
Cap glossiness, bib shape and 'bull-neck' is unreliable due to a lare overlap, as shown in a recent analysis of identification methods (Broughton, RK. Identification of Willow Tit and Marsh Tit in Britain: a review. British Birds magazine, Nov 2009).
Marsh Tit can sometimes show a pale 'wing panel' on the secondaries, similar to Willow Tit, so this should be used with caution.
While many calls overlap, several calls are distinctive: Marsh Tit has a 'pit-choo' call that Willow Tit does not give, often followed by a rapid 'dee-dee-dee'. Willow Tit's version of this call lacks the 'pit-choo' and the dee notes are harsh, long and nasal: 'taaaah-taaaah-taaaah'.
Distribution
Most of England and Wales, although virtually absent from Scotland (only a few in Borders) and none occur in Ireland. Absent from much of Lincolnshire and scarce in the Fens.
Habitat
Mature woodland, usually over 50 years old. Requires a mature canopy with a well-developed shrub-layer. Occurs in conifer or mixed woods where a boundary hedge fucntions as the shrub layer. Occurs at low densities due to large territories - average of 4-5 ha (compared to c.1 ha for Blue Tit). Will use gardens, particularly in late summer/autumn/winter, if they are within 1-2km of woodland.
Diet
Insects and arthropods and seeds. Caches food in late summer and autumn, for later retrieval. Extracts seeds from berries (including hawthorn) and hammers them open. Very fond of honeysuckle and spindle berry seeds. Takes wheat from pheasant hoppers and keen on thistle and burdock seeds, beechmast. Readily visits bird tables if close to their territories, and particularly fond of sunflower seeds and nyjer, but will take almost any seed or nut, as well as fat.
Behaviour
Sedentary, rarely moving or dispersing over 1-2 km. Strictly terriorial from March-June, in pairs, ranging more widely outside the territory at other times with other Marsh Tits or small birds. Agile, inquisitive and intelligent, quite bold. Submissive to Blue Tit and Great Tit, dominant over Willow and Coal Tits.
Reproduction
Song period starts in Febraury, peaking in March/April. Nests in cavities in trees or shrubs, from ground level (among roots/stump) to 10 m. Hole often very small, 25-30 mm. Sometimes uses nestboxes, but they are not preferred (cf Blue Tit) and will not increase the population as density is regulated by social structure. Nest is made of moss, with a neat cup lined with a felty mat of fur. Feathers are unusual. Lays 4-10 eggs (usually 6-9), white with reddish spots, in April. Incubates for 13 days. Young are fed on caterpillars and fledge at 18-22 days in early-mid June, and are fed by their parents for a further 10-15 days. Young then disperse immediately and typically settle 300-1500 m away, immediately defending a territory and forming pairs/social groups if possible.
Nest predators include Great Spotted Woodpecker and, particularly, Stoat and Weasel. Grey Squirrels occasionally, and also Badger and Wood Mouse recorded. Flooding of nest hole not rare.
Population
Declined by 68% between 1965 and 2007. A Red-listed species of serious conservation concern.
Status
Widespread but uncommon, having undergone a serious decline.
Did You Know?
Most breeding pairs remain together for life, and some have been recorded staying together for 6 years. But divorce and bigamy also occur sometimes.