July 19, 2016
Allison (Allie) Balthazor, a Gallery Interpreter at NHMLA, recently had a new family move in next to her apartment. Instead of a U-Haul, all they brought were a few sticks and twigs. Allie lives in an apartment complex in Burbank and not off the grid in a local wilderness, so of course her new neighbors were not humans. They were a mated pair of Mourning Doves (Zenaida macroura)! Footage of female Mourning Dove guarding her nestling in the nest, seemingly unfazed by the urban sirens passing by. Video by Allison Balthazor.
Twigs and branches being set up by Allison’s new neighbor. Photo by Allison Balthazor. Allie shares her entertaining story with us: “The property manager was not happy about them moving in, and he wanted to kick them out. (Maybe it was because they didn’t sign a lease!) Of all the pest problems you can experience in an apartment, I’d much rather live with a Mourning Dove family than with bed bugs ANY DAY! The doves first brought some twigs with them and stuffed them in the case above the fire extinguisher, then they formed them onto a little twig wreath. Shortly after, I saw one egg appear. The next day, when I came back from work, there was a second egg. The parents took turns incubating the eggs, and the chicks hatched, grew and fledged surprisingly quickly. The property manager was happy when they left. But his glee was premature. They returned not two weeks later, built another nest, and are raising a second family.”
Nesting on fire extinguisher at eye level at a semi-indoor hallway. Photo by Allison Balthazor. Kimball Garrett, NHMLA’s ornithology collections manager, says that Allie’s observations are consistent with known Mourning Dove breeding patterns. They only need approximately 30 days between the initiation of the first and second clutches of eggs, and can actually lay new eggs while the first brood of offspring are still being tended. Which is why Mourning Doves are one of the most abundant species in the United States, with a population of 350 million. Human parents, or soon-to-be parents, may be able to learn from these avian team players. The male and female doves work together to make sure their breeding is a success. The male chooses the territory, the mom finds the actual nest site, and the male gathers branches and twigs for the female to construct the nest. Both parents produce crop milk—a highly nutritious secretion from the lining of the doves’ crops—and they consume snails and bone fragments to aid in the production of the delicious baby bird formula. Unlike the ubiquitous Rock Pigeon (or Rock Dove—otherwise known, and loathed, as our common domestic pigeon) that was introduced from Europe into North America in the early 1600s, Mourning Doves are a native dove species in Los Angeles. Pigeons and doves are part of the same taxonomic family (Columbidae). Species known as “pigeons” typically have a heavier build with shorter necks, and broader, more squared-off tails than doves. Interestingly, Mourning Doves are more common than Rock Pigeons inside the NHMLA Nature Gardens, though there are more Rock Pigeons in the surrounding buildings and open lawns.
Mourning Dove nesting in the NHMLA Nature Gardens. Photo by Allison Balthazor. Doves and pigeons are the only birds, other than sandgrouse, that have the unique ability to suck and swallow water without lifting their heads. This may be an anti-predator defense, as they are ground-feeders and need to stay extra-vigilant. Mourning Doves are typically recognized as the lighter colored and pointy-tailed pigeons with wings that whistle in flight. They are often confused with owls due to their cooing “hoo-OOOoo, hoo, hoo-hoo” call. The only other common native Columbidae family member in the L.A. Basin is the Band-tailed Pigeon. Its distribution is centered in the foothills and forests, although many have colonized the suburbs and even downtown L.A. The native Mourning Dove, however, is possibly the most widespread bird in Southern California, which is impressive given how many bird species occupy the region. A few non-natives are becoming increasingly populous. Introduced species that thrive in a new region are usually generalists (flexible diet, habitat preferences, and behavior). Those characteristics allow them to outcompete less flexible native species that have overlapping ranges and habits. Similar to the Mourning Dove, the Eurasian collared dove is an introduced species that has become widespread. One of the easy ways to distinguish between the two species is by looking for the distinctive black collar on the back of the collared dove’s neck. They are also stockier and much paler than Mourning Doves. Eurasian collared doves were accidentally released in the Bahamas in the 1970s and subsequently spread to Florida. Throughout the 1990s and into the early 2000s they spread rapidly across North America, including California. A separate introduction of collared-doves took place in Ventura in the early 1990s (Garrett et al. 2012).
Eurasian collared dove documented on iNaturalist by @nhmordenana. Perhaps, one of the reasons dove species do better in our region is because they aren’t hunted. Mourning Doves are a highly hunted game bird in North America, but L.A. doesn’t have a robust hunting culture, nor is hunting even allowed within city limits. You can now appreciate our common Mourning Dove wherever you go in L.A. If you see a dove, take a moment to appreciate its quirkiness, try to ID it, and send a photo to our L.A. Nature Map. References: Garrett, K. L., J. L. Dunn, and B. E. Small. 2012. Birds of Southern California. R. W. Morse Company, Olympia, Washington. p. 219. Mirarchi, R. E. and T. S. Baskett. 1994. The Mourning Dove (Zenaida macroura). In The Birds of North America, No. 117 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists’ Union.
January 9, 2018
May 10, 2012
On the tails (mammal and bird tails that is) of last week's post, I thought I'd continue to focus your attention on our wonderful new pond. Sam Easterson has set up some of his trusty camera traps next to the waterfall to see who might be visiting the pond. Check out the following images to see what he has found so far. Nighttime is busy at the pond!
Stray cat...sorry, there aren't any fish in the pond yet and no you can't eat them when there are!
Opossum...no tin foil in the pond either. Although these night time endeavors are interesting, I think the action during the light of day is even more so. Over the last few weeks, Sam's traps have captured over 50 images of birds hanging out by the pond.
American Crow, Corvus brachyrhynchos That is one good bath!
Black-headed Grosbeak, Pheucticus melanocephalus, stops by for a moment.
Western Gull, Larus occidentalis, going in for a drink.
Camera shy Swainson's Thrush, Catharus ustulatus.
Male Western Tanager, Piranga ludoviciana For the grand finale, watch three bird species drinking from the pond at once! We've got a Mourning Dove, Zenaida macroura, on the far left, a Western Kingbird, Tyrannus verticalis, center frame, and a Warbling Vireo, Vireo gilvus, doing a fly-by. Want to see more creatures caught on camera trap? No problem, check out lots more pictures and videos on our flickr pool.
December 13, 2017