Our new friend this week is the long-tailed tit.  This bird is widely distributed throughout the palearctic, “a zoogeographical region comprising Eurasia north of the Himalayas, together with North Africa and the temperate part of the Arabian peninsula,” and does not migrate.  The bird is very small, 13-15 centimeters long including its 7-9cm (3-3.5 freedom units) tail, and both sexes are primarily black and white with a bit of pink.  It prefers to live in deciduous or mixed (deciduous and coniferous) forest with a “well-developed scrub layer,” ideally at the edge of a stand of trees.  The long-tailed tit (hereafter the LTT) eats insects year-round, with an occasional seed in the fall.  

Like last week, this bird takes nest-making really seriously.  The nest is constructed from lichen, feathers, spider egg cocoons and moss, comprising over 6,000 individual component pieces per nest.  This is pretty wild, please enjoy this excerpt from Wikipedia I cannot be bothered to paraphrase: “The nest is a flexible sac with a small, round entrance at the top, suspended either low in a gorse or bramble bush or high up in the forks of tree branches. The structural stability of the nest is provided by a mesh of moss and spider silk; the tiny leaves of the moss act as hooks and the spider’s silken thread provides the loops, thus producing a natural form of velcro.^[19] The tit lines the outside with hundreds of flakes of pale lichens to provide camouflage. The inside of the nest is lined with more than 2,000 downy feathers to provide insulation.” 

Despite all of this work, the nests are very vulnerable to predators, with only 17% producing offspring that live long enough to leave.  This may be due to the nests often being less than 3 meters (10 feet) off the ground, but I’m guessing tiny birds that can successfully out-breed an 83% failure rate know the deal.  I’m not their supervisor.  

The LTT (hee hee) has a pretty complex social structure.  Outside the breeding season, the birds form flocks of six to 17 birds, comprising families (parents and offspring from the previous season) and helpers who helped raise the brood.  They will establish territory and defend it form other flocks of LTTs.  Although I couldn’t find any pictures, these tiny birds survive the winter by huddling together for warmth, which is an incentive to form a flock.  They keep from inbreeding by recognizing family members by their call and pitching woo somewhere else.  Because each nest has such a high rate of failure, LTTs whose nest is destroyed by predators may try again if it is early enough in the season.  Otherwise they will join a neighboring flock as helpers.  As many as 50% of nests have associated helpers pitching in, and offspring that were raised with helpers have a higher survival rate than those who were not.  Nesting pairs which go on to become helpers have a higher survival rate than those that opt to try again, assumedly because teaming up allows them to expend less effort overall.  Certainly less effort than building a 6,000 piece nest twice.  However, “failed breeders” who do try again have a higher rate of success than those who opt to be helpers, so its a bit of a tradeoff.  

The LTT is very common throughout its range, and is not considered threatened by any prominent conservation body.  They are extremely vulnerable to cold, but population numbers appear to quickly bounce back after a harsh winter.  

Have a good weekend, everyone.  Be good to each other, and remember, rest is not a reward.  You don’t need to earn self-care, you just get to do it.

Links: https://tinyurl.com/mwjs2r9w, https://tinyurl.com/3yvvn5mj, https://tinyurl.com/yc7rk2kz, https://tinyurl.com/yhsz6tp3