The Surprisingly Complex Social Life of the Wild Turkey

This week, as your thoughts turn to roasted turkey with all the trimmings, take a moment to ponder the beast in your feast. While domesticated turkeys are only a few hundred years removed from their wild brethren, behaviorally they are quite different. The wild turkey has a sophisticated social system that rivals that of lions or primates.

Note: an edited version of this appears (or will soon appear) on the Ethogram, an outreach blog for the Animal Behavior Graduate Group at the University of California Davis.

A team of two male turkeys courts a female.

Let’s start with the wild turkey’s breeding system. Unlike about 90% of birds, in turkeys there’s no bond between males and females. In fact, the breeding system defies most traditional organization schemes biologists have proposed, falling somewhere between harem defense in which one male can guard several females (think a big bull elk and his female herd), and a lek mating system where  a female can choose among several males. Female turkeys may be attended by a team of two or more males who act together to try to woo the hens and keep other males away; other teams or solitary males also may orbit the female flock as it wanders around. More on these teams below.

Turkey nest in tall grass

Wild Turkey Nest

The females are far from passive players in all of this. Turkey hens can, and do, mate with more than one male. For more on what females are looking for in a mate, check out the work of Dr. Richard Buchholz, including a recent summary airing on Science Friday (Spoiler Alert: it’s all in the snood). Wild turkeys are also intraspecific brood parasites, meaning one female can lay an egg in the nest of another female of her own species to raise. Putting all this together, the poults (chicks) from a turkey nest can be any combination of full siblings, maternal half-siblings by a female mating with two or more males, unrelated nest-mates from another female’s eggs, and even occasional paternal half-siblings if the other female mated with the same male! And you thought your family was complicated… In spite of all this variety, overall about half of nests in a Carmel Valley study[1] resulted from only one female mating with one male, and the completely unrelated offspring in a nest were pretty rare.

The fact that most poults in a nest are usually close relatives becomes important for the next part of the story– what’s going on with those teams of males. Why one animal should help another is one of the fundamental questions of evolutionary biology- shouldn’t males be trying as hard as they can to pass as many of their own genes into the next generation? In the 1960’s, PhD student Charles Watts, working in a Texas turkey population, proposed a solution involving a newly emergent concept called kin selection [2]. If the turkey teams were composed of brothers, these males would share many of the same copies of their genes because they are from the same parents. Thus even if one of the brothers fails to mate, he can still pass on portions of his genome by helping his closely related teammate to reproduce. However, Watts’ evidence for kin selection was circumstantial, attempts to replicate the study failed, and eventually Watts’ own committee member published a scathing critique of the idea [3].

Here are two videos showing both the cooperative courtship of males and the defense of females.

Confirmation of the kin selection hypothesis for cooperation in male turkeys had to wait almost 40 years. With the advent of DNA analysis that allows researchers to figure out which males were passing on their genes, as well as whether males were related or not, it was finally possible to test whether having team-mates leads to more offspring for males, and whether the teams are close kin. When the genetic data were analyzed [4], it was found on average that at most one male per coalition was able to mate, but that on average these males fathered several times as many offspring as solitary males who didn’t have a helping team-mate. Additionally, these coalitions were related on average between the level of half- and full brothers. These observations provided all the information necessary to evaluate Hamilton’s Rule, the simple cost-benefit equation proposed by famous evolutionary biologist William Hamilton to determine whether the gain in indirect reproduction (i.e. that gained by helping relatives reproduce more) is enough to offset losses to an individual’s own reproduction. For the male turkeys, it turns out the subordinate, non-breeding teammates actually pass on more gene copies by helping their close relative to reproduce than if they left the team and went off on their own to try their hand at solitary display. With this result, turkeys provide a powerful example of how even counter-intuitive behaviors like self-sacrifice can evolve.

Summing all this up, wild turkeys live in societies that feature both intense competition and surprising cooperation among males, along with a host of female mating and egg-laying strategies. Tantalizing anecdotes point to even further layers of complexity in how turkey populations are organized. Watts observed occasional battles between large flocks of turkeys; a more recent observation of this phenomenon described it using a West Side Story analogy, as if the “Sharks and Jets” were facing off. Unfortunately these events are so rare that we don’t yet know how they are organized or what the fight is all about. Regardless, turkeys have a lot to teach us about how and why animals do the things they do.

[1] Krakauer, A.H. 2008. Sexual selection and the genetic mating system of Wild Turkeys. Condor 110(1): 1-12. [link to journal]

[2] Watts, C.R and A.W. Stokes. 1971. The social order of turkeys. Scientific American 224: 112-118.

[3] Balph,D.F., Innis, G.S., and Balph, M.H. 1980. Kin selection in Rio Grande turkeys: A critical assessment. Auk 97(4): 854-860. [link to journal]

[4] Krakauer, A.H. 2005. Kin selection and cooperative courtship in wild turkeys. Nature 434: 69-72. [link to journal]

2015 Field Assistants Wanted!

It’s been a while since I’ve posted anything, so this seems like a good time to dust off the blog!  We’re starting to plan for the 2015 field season. Here’s the posting for the field crew. If you or someone you know would be a good fit for Team Grouse, please have them apply!

FIELD ASSISTANTS (5+) needed approximately March 3 – May 5 for investigations of the behavior and ecology of Greater Sage-Grouse near Lander, Wyoming and the scenic Wind River Range. The projects are part of a larger effort in Prof. Gail Patricelli’s lab at UC Davis to understand the environmental and social factors shaping sage-grouse display behaviors- see the following websites for more information ( and ( Assistants will use video and audio recording technology to support an NSF-funded study of courtship dynamics and display plasticity on the lek. Duties include some or all of the following: maintaining camera and acoustic monitoring equipment, observation of basic courtship behavior and lek counts, GPS surveying, habitat characterization and vegetation sampling, capture of adult sage-grouse, radio-telemetry, data entry, and some computer and video analysis. Assistants must be flexible in their needs and comfortable living and working in close quarters in a remote field station, and able to work in adverse field conditions (mainly MUD, WIND and COLD).  Work will be daily and primarily early in the morning, with afternoon and night work required as well.  Applicants must have a valid driver’s license, basic computer skills, and have participated in at least one field biology project in the past. Wilderness First Aid or First Responder, and previous experience/certification with off-road driving and/or ATV’s is preferred but not required. Individuals with previous sage-grouse capture experience especially encouraged to apply. Must be able to show proof of United States employment eligibility. Assistants will receive a total stipend of $1500 (~$750/mo) plus food and shared housing, but need to provide their own transportation to Lander and their own personal gear.  Please send a single PDF containing a cover letter, resume, and contact info for two (2) references to: Alan Krakauer, Department of Evolution and Ecology, University of California Davis, One Shields Avenue, 2320 Storer Hall, Davis, CA 95616, or preferably by email to ahkrakauer [at]  The positions will remain open until filled, and review of applications will begin immediately.


Oddball Science

As someone who studies a bizarre bird using high-tech methods (including robots), I sometimes get the question “Why?” In some cases people are interested in my research questions and why I am passionate about it, but sometimes “Why” can mean “Why should my tax dollars go to support this?” Government funding for scientific research is always under scrutiny, particularly now.

My friend and colleague Patricia (Patty) Brennan has faced questions about the rationale behind her research as much or more than any evolutionary biologist I know. Patty studies (among other things) the coevolution of male and female genitalia in ducks, and her work has been highlighted in the popular media both as exciting, valuable, cutting edge research as well as wasteful spending on frivolous questions. She responded with a fantastic defense of “oddball” science in Slate. She also made her case at a Science Cafe event in Massachusetts (click for video). If I can paraphrase the article and the lecture, we should fund basic science because

  1. Basic science is the foundation of applied advancement- almost nothing in our 21st century technology and medicine would exist without discoveries from basic science, but those links are often fortuitous and we need to cast a wide net (not that all research should be funded, but it is impossible to predict where the important discoveries will occur).
  2. Scientific research is currently funded at embarrassingly small levels compared to other countries- it is a cheap expenditure that pays dividends down the road.
  3. A necessary product of research is education and outreach by scientists (it is a required component of almost all basic science grants), which helps to increase scientific interest and literacy in the public and inspire the next generation of scientists. More funding would mean more of this – see point 2.
  4. It’s pretty neat to figure out how the world works.

Lab Accolades May 2014

Some hearty congratulations are due for Patricelli lab members!

First, our honors student Rebecca was awarded the College of Biological Sciences citation as one of the top graduates across all biology majors in the college. She has been working with us for several years, most recently on a thesis project to examine vocal behavior in sage-grouse in response to changes in female behavior. She presented this at last month’s Undergraduate Research Conference, and is completing her thesis soon.

Gail, Rebecca, and Anna celibrate Rebecca's award.

Second, recent Ph.D. (and former Wyoming field assistant) Conor Taff received two major honors yesterday. First, Conor’s dissertation was named the Merton Love Award for best dissertation across the ecology graduate groups here at UC Davis. Given the large number of high-quality graduate students here, this is an enormous distinction! He will be giving the Ecology and Evolution seminar next week. Second, he has been given a prestigious young investigator award by the Cooper Ornithological Society [not the American Ornithologists' Union as I originally wrote]. Conor’s dissertation project was an integrative study of development and sexual signalling in a warbler called the Common Yellowthroat. You can read more about it on his website.

Congrats to both Conor and Rebecca!

2014 Field Season Recap

Getting muddy out there...

We survived the pack-up and clean-up, and are back in Davis. Once again, Wyoming made this somewhat challenging. There’s been a long-standing joke with our local contacts that runs something like “winter isn’t over until the California ‘Chicken’ crew leaves.” This originated in our first few years, when we always seemed to leave town with a winter storm on our heels. This year, the weather gods seemed to want to revisit this joke. Our pack up week saw 2 decent storms roll through Fremont County. Neither left insurmountable amounts of snow, but we ended up having to pack everything up in a cold muddy morass. Adding to the list of why field work is not always glamorous: scrubbing out dirty trashcans in 32 degree weather with a driving snow, and laying on ones back in a mud-puddle to secure a tarp around a lumber pile. The late season storm did provide some opportunities though, such as seeing the now-blooming paintbrush poke through the snow.

Paintbrush in the snow

We had a break in the weather on our final weekend, and traveled with Stan to Oregon Buttes, a scenic and historic area south of South Pass. Turning south of the highway between Farson and Lander, the first stop was a marker for the Oregon Trail, which comes through that (relatively) low and flat region of the Continental Divide. Onward and we come near the Oregon Buttes themselves, which we got to view through weather oscillating rapidly between snow, clouds, and sun.

Oregon Buttes

Finally we worked our way towards the badlands area of Honeycomb Buttes. The flatlands approaching the buttes held almost comically picturesque herds of wild horses.

Wild horses

The rockhounds among our group (everyone) collected beautiful pieces of petrified wood, fossilized algae, and agates. Finally onto the badlands, which were sprinkled with shards of fossilized turtle shell. It was a fantastic day to explore some different sage-grouse habitat and see a new part of the local scenery.

Honeycomb Buttes

The drive back was uneventful. We made it to Elko, NV as our halfway point, and bypassed the Cabela’s superstore in Reno in the interest of beating Sacramento rush-hour traffic.

Looking back on the 2014 field season, how did it go? It was a particularly exhausting season, with so many new things to figure out, and a large crew to manage. In some ways it felt like our first season when everything was new, although with the pressure and expectations that come with a lot of goals and the knowledge that we are mid-grant with limited time to accomplish our objectives.

Fembot "Salt" approaches the target area as males get excited.

That said, I think we kicked butt this year. We crossed off several major items in our 2014 field effort. First off- the robot experiments were a real success. Anna did a wonderful job in planning these out, and the birds and weather generally cooperated. We had two target areas on each lek, and were able to run at least 3 different trials at each one. On some days both Gail and I piloted robots at the different leks- a first for us (and the first time I’d gotten to drive during a real experiment). Anna was able to train James to be a second experiment director for these dual-experiment days. Hopefully our data will allow us to look both for seasonal trends in courtship effort as well as differences individual male persistence. We will only know the results once we analyze the video and audio data collected along with the experiment, but our impression was that everything worked pretty well this year.

Secondly, we accomplished a whole suite of interrelated objectives as part of the encounternet tag work. Step one of this was to actually capture birds and get tags on them. Frank and Julia got up to speed on this really quickly, and we ended up catching close to 30 birds. Not sure what our average was, but I’d guess close to two birds per night which is not bad with for the relatively small crew we had available to go catch birds on a given evening. Getting the harnesses on the birds had stymied us in the past, but this season we got the hang of it (the rump mounts are a little tricky to fit, and will fall off pretty much immediately if they aren’t attached properly).

With tags on birds, we were ready to tackle the encounternet system itself. With some trial and error and updated versions of the firmware supplied by John Burt, we managed to work on power management of the tag and positioning of the receiving basestations. We ended up with four males for which we could get hourly GPS fixes along with accelerometer activity samples coincident with those fixes. Much thanks to Sean and Sam for building some of the antenna mounts we used.

Finally, with the GPS data flowing in, we could start to crack the foraging ecology questions. Julia was instrumental setting getting an easy protocol for moving  the GPS data from our Google Earth plots onto our GPS. The tags seemed very reliable in pointing us to areas heavily used by the birds, and with Jen Forbey’s help, we became adept at taking samples of the sage and making quick assessments of the habitat at the activity site. We also did lek-based assessments to measure foraging quality at areas surrounding 6 of our leks.

These were the main goals, but we also tackled some auxiliary projects this year. In conjunction with the sage-sampling work, we looked took a series of photographs of various sage-grouse sign (browse marks and poop) to look at how it aged over a period of days. This will help assure us we can identify very recent grouse activity from older sign. Second, we tackled the buttprint aging project again- Sam got started on this early in the season and so this year we’ve managed to save multiple photos for a number of individuals. Combining last year’s data, hopefully we can answer whether it’s possible to reliably age second-year birds based on a distant picture of their tail, and whether this is easier to do early or late in the season.

We accomplished all of these research goals while developing a completely new workflow for our video data. This year we made the transition away from tape cameras and recorded all of our video in full digital format on SD cards.

All in all, a very productive year! Many thanks again to our crew for all their hard work this season!