Friday, April 17, 2015

The Ultimate Reality TV - Live Nest Cams! (a.k.a. Theropods/Birds Do It, Bees Do It)

Hello Dear Readers!

Excuse me while I clear the digital tumbleweeds from my blog. Strange Woman is in full-tilt writing mode right now: I have two papers with fast-approaching deadlines, and thesis chapters to write. If all goes well, I may be finished my degree by the end of the year.

Be they papers or thesis chapters (also known as future papers), this means I'll be spending a great deal of time at my computer, sitting and writing and drinking more Earl Grey tea than is good for a person. I've mentioned in previous posts that I have a rather distracted part of my brain that insists on being entertained while I'm writing. Since I have neither cable nor satellite (and haven't yet taken the Netflix plunge), and since there are only so many times I can re-watch what I refer to as my writing movies, I have become an unabashed live nest cam addict.

It's not only the up close view of the personal lives of birds, or the rapid transition from a helpless ball of fluff to a fully functioning bird of prey (or of fish, or of flower...) that fascinates me about nest cams: being an unapologetic bird geek, I love being able to spread my love of the avian world around. A peek into the usually secret lives of birds, from egg laying to leaving the nest, and to be able to watch parental care of deadly predators (in the case of our birds of prey), it gives me a sense of connection with nature that I miss when I am office-bound. Teaching, and getting kids interested in the natural world is another interest of mine. Nest cams are great teaching tools, and the Cornell Lab (see link below) provides wonderful tutorials on how to incorporate live nest cams in to biology lessons.

I also have a paleontology interest in the nesting behaviors of birds. Birds are modern-day (or extant, for the technical term) theropod dinosaurs! There is great fossil evidence that theropod dinosaurs also engaged in nest building, active egg incubation, and parental care that is similar to what we see in modern birds. The best example (and best-known science story) of bird-like brooding in theropods is with Oviraptor philoceratops (the egg thief that loves ceratopsians). This story begins with the initial interpretation of thievery to explain its presence on a dinosaur nest full of eggs (thought to be the eggs of Protoceratops), and an associated skeleton of a predatory dinosaur with a toothless beak: both pieces of information led the researchers of the day (Osborn 1924) to suggest that Oviraptor was well-suited - and took advantage of - a diet that included eggs. Norell et al. (1999) examined an oviraptorid skeleton found in a similar position as the original Oviraptor specimen - a skeleton closely associated with a clutch of fossil eggs.

Figure 1 from Norell et al. (1999). Here's a link to the paper. Free to download from the American Museum of Natural History Research Library, along with many others!

The study of eggshell is a sub-discipline within paleontology much like ichnology: by studying the surface and microscopic details of eggshell, researchers can identify which animals laid the eggs. Dr. Darla Zelenitsky is an expert in the study of dinosaur egg shell and reproductive traits in dinosaurs: check out the research page for Evolution of Reproductive Traits in Theropods, and feast your eyes on an image of an oviraptorid skeleton with eggs actually inside the pelvic cavity!

(Note: Unfortunately, there are also many, many theropod eggs for sale online. These mostly come from Mongolia, and they are illegally removed from the country. As I've stated before, buying specimens like these supports fossil poaching and other illegal fossil-related activities. Yes, bad pun alert: the eggs you see for sale online are poached.)

To return to the story of Oviraptor, Norell et al. used the shape and texture of eggs that contained embryonic oviraptorid bone found in different parts of Mongolia and compared those eggs to the eggs found in a nest topped with an Oviraptor skeleton. Sure enough, the morphology of the eggs matched! These Oviraptor specimens did not die in the act of thieving a Protoceratops nest - they were incubating their own eggs. Of course, that does not suggest that Oviraptor didn't ever rob nests of other dinosaurs - modern birds, such as corvids (crows, ravens, magpies, jays), raid the nests of other birds. Food is food. However, what these nests and skeletons do show is that bird-like nest building and brooding are not restricted to our modern theropods - nesting is an old, old behavior for dinosaurs.

There is more evidence of nesting behavior in dinosaurs, but here is a very short list. Varricchio et al (1999) describe a nest attributable to the Late Cretaceous theropod Troodon formosus, and document both the crocodile-like and bird-like traits seen in the nest. The nesting hadrosaurs (duck-billed dinosaurs) from the Two Medicine Formation in Montana are another famous example (Horner and Makela 1979). Nests have also been well-documented for titanosaurid sauropods (Chiappe et al. 2004, for just one example).

Because of the increased information we have on the nesting behavior of dinosaurs, paleontologists are able to examine other aspects of dinosaur reproduction, such as when dinosaurs became sexually mature (check out the Erickson et al. 2007 paper here), and how active hatchling dinosaurs may have been based on the microstructure and development of their bones (Horner et al. 2000). There are even data that suggest Cretaceous snakes may have preyed upon hatchling sauropods: check out the paper and images by Wilson et al. (2010) here. Cretaceous nesting biology was just as complex and fascinating as is modern nesting biology!

If you want to see some modern theropods nesting and raising their young, here are the live nest cams I watch. All of the cams listed here have a bird incubating eggs, young in the nest, or are being actively investigated by potential nesters. This list is by no means an exhaustive list of all live nest cams everywhere - there are nest cams up all over the world, and this list is admittedly Canada and United States focused. If you have a favorite nest cam, please share the link in the comments section, and I'll add it to this list!

Cornell Lab of Ornithology Bird Cams - Here you will find great educational resources for incorporating Bird Cams in to classroom lessons! Their bird cams are:
  • Great Horned Owls, Skidaway Audobon - On air. The owls have fledged, but there are two Osprey that have been visiting the now empty nest. Will the nest be repurposed? Watch and find out!
  • Laysan Albatross, Anonymous - On air! Chick active and growing (with the occasional rooster prancing across the stage). A different kind of nesting strategy - ground-nesting! You also get to see parents feeding the chick, and adults performing display behaviors.

American Kestrel Partnership Bosch KestrelCam - On air, and there may be five eggs in the nest! Kestrels are cavity nesters, and you can find instructions on how to set up a nest box for American Kestrels here.

The Peregrine Fund Peregrine Falcon Nest Cam, Boise, Idaho - On air. Mother is on the nest at this writing. It is not uncommon to find Peregrine Falcons living in urban areas, as these birds of prey are most often seen in a mountain habitat and are cliff-nesters. This is why we find Peregrine Falcons nesting on ledges of tall buildings.

Alessondra's OKC Great Horned Owl-Cam - Great Horned Owls decided that a planter makes a great nest! The nest cam was set up by homeschooling family and used as an educational tool. Off air now that fledging has taken place for the year. Will they return for 2016? [Note: if you watch the farewell video, the starting theme music and sad tones had me worried that the owls had died. Happy Spoiler: they successfully fledged.]

Pennsylvania Bald Eagles, Hanover, Pennsylvania Game Commission - On air, and two chicks (looking quite theropod-y) are in the nest!

Bella Hummingbird's Nest Cam, La Verne, California - On air, and the tiny nest is crammed full of two Allen's Hummingbird chicks!

Happy Nest Viewing!


Chiappe LM, Schmitt JG, Jackson FJ, Garrido A, Dingus L, & Grellet-Tinner G. 2004. Nest structure for sauropods: sedimentary criteria for recognition of dinosaur nesting traces. Palaios 19(1):89-95.

Clark JM, Norell MA, & Chiappe LM. 1999. An oviraptorid skeleton from the Late Cretaceous
of Ukhaa Tolgod, Mongolia, preserved in an avianlike brooding position over an oviraptorid nest. American Museum Novitates 3265:1-36.

Erickson GM, Curry-Rogers K, Varricchio DJ, Norell MA, & Xu X. 2007. Growth patterns in brooding dinosaurs reveals the timing of sexual maturity in non-avian dinosaurs and genesis of the avian conditio. Biology Letters 3(5):558-561.

Horner JR & Makela R. 1979. Nest of juveniles provides evidence of family structure among dinosaurs. Nature 282:296-298.

Horner JR, Padian K, & de Ricqlès A. 2001. Comparative osteohistology of some embryonic and perinatal archosaurs: developmental and behavioral implications for dinosaurs. Paleobiology 27(1):39-58.

Osbom, HF. 1924. Three new Theropoda, Protoceratops zone, central Mongolia. American Museum Novitates 144:1-12.

Varricchio DJ, Jackson F, & Trueman CN. 1999. A nesting trace with eggs for the Cretaceous theropod dinosaur Troodon formosus. Journal of Vertebrate Paleontology 19(1):91-100.

Wilson JA, Mohabey DM, Peters SE, Head JJ. 2010. Predation uponh atchling dinosaurs by a new snake from the Late Cretaceous of India. PLoS Biol 8(3): e1000322. doi:10.1371/journal.pbio.1000322

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