Birds and mosses - a collection of sorts

Photo by Tim Laman

Birding is being reported as the second most popular hobby in America. For years bryologists and birders (and ornithologists, too), have observed birds using mosses for a variety of purposes, chief among them to line their nests.
This posting is a collection of references to interesting studies and amusing anecdotes about birds using mosses for nesting, in mating rituals, and in apparent, but birdlike, acts of aggression. 
In addition to the well-documented observations of mosses being used as padding and lining in bird nests, mosses are known to have antimicrobial properties, which is another reason birds are believed to line their nests with mosses.

Photo by Tim Laman

In the first article listed below from National Geographic, mosses are part of the decoration used by male bowerbirds to attract females to a mating site.  Enjoy the story and the images.

Build it and they will come, National Geographic, July 2010.
To win choosy females, male bowerbirds swagger, croon, and… decorate.
_____

Which Bird Made That Nest? Northern Woodlands 
by Bernd Heinrich, December 28, 2009. Illustration and images by Bernd Heinrich.

Cedar Waxwing on Arrowwood

Cedar waxwing Bombycilla cedrorum

Cedar waxwings nest in small evergreens or deciduous trees in edge habitat. The nest cup is untidy on the outside like a robin’s and of similar size, but it lacks the mud cup and is typically garnished on the outside with lichens and/or moss.
Red-breasted nuthatch Sitta canadensis
Red-breasted nuthatches build substantial nests of moss, down, and fibers in their nest cavities, whereas woodpeckers never put in any nest material.
Winter wren Troglodytes

All wren nests are domed, with a small entrance hole at the side. Those of the winter wren are most commonly garnished on the outside with green moss and small spruce or fir twigs. Although the wrens may place their nest under a stream bank, in hanging moss close to the ground, or in a small, densely branched tree, they are most commonly found in root tip-ups of wind-blown trees.
Ruby-throated hummingbird Archilochus colubris
Ruby-throated hummingbirds garnish their walnut-sized nests with lichens to “mimic” bumps on limbs. Nests are lined with soft white plant down. The only nest that is similar in habitat, placement, and appearance, though it is substantially larger, is that of the wood peewee.

See additional references and a series of illustrations and photos at the Northern Woodlands website. Bernd Heinrich is professor emeritus of biology at University of Vermont. His book, Nesting Season, was published in March 2010.
_____

Incidence of Nest Material Kleptoparasitism Involving Cerulean Warblers
by KC Jones, 2007, The Wilson Journal of Ornithology
Abstract
We document 21 observations of interspecific stealing of nesting material involving Cerulean Warblers (Dendroica cerulea), Red-eyed Vireos (Vireo olivaceus), Blue-gray Gnatcatchers (Polioptila caerulea), Northern Parulas (Parula americana), Black-throated Green Warblers (D. virens), American Redstarts (Setophaga ruticilla), and Orchard Orioles (Icterus spurius) that occurred during studies of Cerulean Warbler breeding biology. These incidents involved a variety of combinations of nest owner and nest material thief suggesting that each of these species is both a perpetrator and recipient of this behavior in our study areas. Kleptoparasitic incidents occurred at all stages of the nesting cycle from nest-building through post-fledging. Two possible motivations for this behavior are related to saving time in finding nest materials and collecting this material for nest construction.

Kelly C. Jones (1), Kirk L. Roth(2), Kamal Islam(1,3), Paul B. Hamel(2), and Carl G. Smith III(2), 1:Department of Biology, Ball State University, Muncie, IN 47306, USA. 2: USDA, Forest Service, Center for Bottomland Hardwoods Research, P. O. Box 227, Stoneville, MS 38776, USA. 

3: Corresponding author; kislam@bsu.edu
_____

Making a nest in a bird box (with webcam)
View video images of a nesting Blue Tit build and hatch eggs inside a nest box. A Blue Tit arrived only a day after the box up on the side of a workshop!

Courtesy Ria3/flickr

Another Blue Tit building a nest with mosses

Birds of the Great Plains: Family Tyrannidae (Tyrant Flycatchers)
by Paul A. Johnsgard http://digitalcommons.unl.edu/bioscibirdsgreatplains/38/
_____

Birds in Forested Landscapes, Hermit Thrush (Catharus Guttatus)
http://www.birds.cornell.edu/bfl/westernbirds9.html
Nest: The female builds the nest alone. Compact but bulky nest made of twigs, bark strips, mosses, ferns, and grasses. Lined with conifer needles, rootlets, and plant fibers.
_____

CAROLINA CHICKADEE
PARUS CAROLINENSIS Audubon  
www.Birdzilla.com  Contributed by Edward Von Siebold Dingle
When the hollow has been excavated, nest-building is begun, as Dickey says, "with thick foundation of moss (Hypnurn) – strips of yellow and brown bark, a few strips of yellow grass and grass culms or panicles, a little thistle down or milkweed pod down, and then such bird feathers as those of sparrows, bluebird or of the parent. The cup is well padded with silvery milkweed or thistledown, animal hair, red hair of the cow, gray fur of the cottontail rabbit and fur also from deer, mice, and other Mammalia."
...
Erichsen (1919) writes: "Simultaneous with the appearance of the down on the stalk of the cinnamon and royal ferns, which occurs during the middle of March, the chickadee begins nest-building, for this material is used largely by the birds in lining their nests. As far as my observations go, the birds, in gathering the down, always begin at the top of the stalk and work downward. The green moss that collects on the trunks of certain species of hardwoods is also used to a considerable extent, being always placed in the nesting hole first, and upon it the down is deposited.”
_____
The following excerpts are from a Bryonet exchange on “Mosses for Nests.”Bryonet is a service of the International Association of Bryologists (IAB)

I have always assumed that the damage done to the moss sward on my garage roof was caused by birds rootling about, looking for insect food. However, a birding friend showed me some video footage yesterday in which a pair of male blackbirds (Turdus merula) were squabbling, presumably over territory. One of them was quite clearly picking up clumps of moss and tossing them at the other one, presumably as a form of aggression displacement activity.  Is this a well known 'use' of moss in the avian world?
_____
I observed in Tanzania, Uluguru Mountains, a nest of a small bird purely made of Orthostichella pandurifolia, which is a common hanging epiphyte of the area.
_____
In Kenya, I have collected a used and fallen bird nest with Papillaria africana (moss still living and green).
_____
I poked through 7 dipper nests from areas around Juneau and found 30 moss and 5 liverwort species, a few of which I only got to genus, plus some unknowns. In most cases the bryophytes were just a trace among the other nest materials, but most nests had quite a few species. The number of species/nest were: 1, 7, 10, 11, 13, 14, and 16 (+ 5 unknowns) respectively. The list is lengthy so I won't include it here.
_____
A few years ago, I identified mosses in dipper nests from somewhere in northern Idaho for a lichenologist colleague. Surprisingly, I found only one species, Scouleria marginata, not the much more common S. aquatica. They, apparently, selected the stronger moss even though uncommon to rare.
_____
D. H. S. Richardson, in his book The Biology of Mosses, gives a list of 53 British birds that incorporate moss into their nests (Table 7.1, p. 113). He also mentions a Virginia study that documents 60 different mosses found in the nests of 11 birds (BREIL, D. A., AND S. M. MOYLE. 1976. Bryophytes used in construction of bird nests. Bryologist 79: 95-98. CHAPMAN, F. M.)
_____
Miscellaneous contributions
Gustavo Tomás, working at the Netherlands Institute of Ecology, has collected moss samples from a large number of blue tit and coal tit nests from a woodland in the East of the Netherlands. I have been helping him identify the mosses (he is an ornithologist). We have not done much analysis yet, but it looks like we can already draw some conclusions. The most common species is Hypnum cupressiforme, which is common in the area. However, other locally common mosses are less common in the nests (so the birds clearly select certain species), and also it looks like different species are used in different parts (top/bottom) of the nest.
_____
In the late 1960s, when I was working on northern Ellesmere Island (ca. 81°N), in the High Arctic, I identified bryophytes from 47 bee nests (mostly bumblebees if I remember correctly), for an entomologist colleague, and the results were surprising: individual nests had from 2 to 14 species of bryophytes present, usually about 6 or 7; at least 56 spp. of mosses and 6 spp. of liverworts were represented, i.e. used in at least one nest; the most frequent species used (found in 19+ nests) were Distichium capillaceum, Ditrichum flexicaule, Bryum (usually tiny more or less unidentifiable scraps), Campylium arcticum, Drepanocladus revolvens (excuse the outdated nomenclature!) and Orthothecium chryseum, all common in the region.
_____
I've run across a reference that as many as forty different types of birds use mosses in constructing their nests. I've certainly seen different types of birds "stealing" mosses from my yard for this purpose. However, the other day while at a client's home in Cashiers, NC, I was delighted to document Thuidium delicatulum in the nest of a Carolina Chickadee located in an English Boxwood shrub.
_____
Nests of this species are composed mainly of bark fiber, .... Red-eyed Vireos have been documented to use all of the same materials as Cerulean Warblers, with the exception of moss, in their nests (Harrison 1975, Ehrlich et al)