by Stefan Nelson | RGS & AWS Forest Wildlife Specialist and Sam Lau | RGS & AWS Integrated Habitat Biologist
Three Ways to Determine Woodcock Gender
There are several ways to determine the sex of an American woodcock, although these methods should only be used on birds at least one month old or older. For the most accurate determination of sex, it’s best to use a combination of the methods below as individual methods may sometimes be unreliable. It’s also good to remember that females are typically larger than males.
Two features on the wing can be used to help determine the sex of a woodcock. The first method involves measuring the widths of the outer three wing feathers (primaries) 2 centimeters from the tip and adding them together. If the sum is >12.6 millimeters, the bird is a female and, if the sum is <12.4 millimeters, it’s a male. If the measurement falls between 12.4 – 12.6 millimeters, then it’s important to use another sex determination method (see below). Please note that an extremely precise tool such as a metric laser calipers is needed for this technique and, as such, is unlikely to be utilized in most cases.
Another technique to determine woodcock sex using the wing is to measure the wing chord length. This is the length from the longest primary feather’s tip to the “wrist” joint of the wing. Feeling the wing will allow you to notice a small notch (the “wrist”), which is where this joint is located. Use the table to determine the sex:
| Wing chord measurement | Sex | Accuracy |
| <125 millimeters | Male | 100% |
| 125 – 127 millimeters | Male | 95% |
| 128 – 138 millimeters | Uncertain | – |
| 139 – 145 millimeters | Female | 95% |
| >146 millimeters | Female | 100% |
The length of the bill can also be used to determine a woodcock’s sex by measuring from the tip of the bill to where the top of the bill enters the skull. In case you’re in the field and have bagged a timberdoodle, but for some reason forgot your metric ruler, a dollar bill can be used as a quick and dirty method to determine the sex. Slide the short (width) end of your greenback into the open bill of the woodcock all the way back until it can’t slide in anymore. If the woodcock’s bill is shorter than the width of your dollar, it’s most likely a male. The actual width of a U.S. dollar is about 66 millimeters, which falls into the 95% male category in the table:
| Bill length measurement | Sex | Accuracy |
| <64 millimeters | Male | 100% |
| 64 – 66 millimeters | Male | 95% |
| 67 – 68 millimeters | Uncertain | – |
| 69 – 71 millimeters | Female | 95% |
| >72 millimeters | Female | 100% |
The last way to determine the sex of a woodcock is by weight. This can be done using a small kitchen scale. Adult birds that weigh >195 grams are most likely female and adult birds that weigh <155 grams are most likely male. However, weight should not be relied upon as a sole determining factor as woodcock weights fluctuate dramatically between – and within – seasons. For example, both male and female weights peak in November and are their lowest around February; however, weights may be 20 to 40 grams lighter in mid-September compared to early November. Additionally, juveniles from late broods will be lighter than juveniles from earlier broods and birds from drought areas will likely be lighter than those in areas with normal moisture levels. Heavier birds are not necessarily migrants (versus residents), but, in fact, are most likely females.
Two Ways to Age Woodcock
Like most birds, woodcock can be placed into two age categories: juveniles and adults. Juvenile birds are in their first year of life (under one year old) whereas adults are more than one year old. Distinguishing age can be done two ways – both involving the wings.
Come fall, look to see if the outermost three primary wing feathers are missing or very short. If so, it indicates that they’re about to or are in the process of growing back following the molt. If this is the case, the bird is an adult as juveniles will not have molted their outermost primary feathers yet. Molting timing for birds is variable; however, and it’s more likely that a bird in the fall will have its outer three primary feathers fully present. If it does, move on to the next identification method.
Extend the wing and count out to feathers 15 to 18, starting with the outermost primary feathers and counting towards the body. Take special care to look at the ends/tips of the feathers. Feathers 15 to18 in both adults and juveniles have a thin buffy/tawny outline, which borders the outside of the feather. Juvenile feathers should have a distinct dark brown-black band separating the buffy tip from the mottling below and mottling should be symmetrical on both sides of the feather midline. Adults won’t have that dark band present and the mottling will be asymmetrical across the feather midline. Unfortunately, there is a fair amount of variation among wings and this technique will take time and practice to master. Looking at clear photos of adult versus juvenile wings can be a helpful start.
Using Age and Sex in Research
Research can provide valuable data not only to wildlife managers, but to those who enjoy wildlife as well. Humans live to learn and adapt as time moves on. Through trial, error and observation, we develop an urge to be – and do – better. Doing better for wildlife means conducting more research to mold the way we manage habitat and specific regulations for each species.
The American woodcock is full of wonders. It’s a chubby shorebird with large eyes that lives in young forests with a specialized diet of earthworms. We know these unique characteristics about woodcock through observing their behaviors over time. Research on woodcock and other species has drastically improved in recent years and it will continue to do so. While years of data and observations build up to decades, likewise, so do our knowledge and research techniques. Banding migratory birds like waterfowl, shorebirds and songbirds can provide vital information for wildlife biologists. Whether a banded bird is recaptured by a researcher, spotted through binoculars by a birdwatcher or shot by a lucky hunter, the data they report from that band informs us of age, sex, species and travel distance.
Currently, there are a few woodcock banding programs going on throughout their range. Both adults and juveniles are banded through a variety of capture methods, including using nets and pointing dogs. Band recoveries are few and far between with this species, but a mist net or a fortunate hunter will pick one up every now and then. Though bands have played an instrumental role in woodcock research and management, advancing technologies are rewarding us with more distinct data. GPS transmitters are now being used by researchers. While these valuable transmitters vary in the amount of data they can supply us with, the data collected gives us more accurate representations of migration routes and habitat utilization through various location points transmitted to us at random or scheduled times.
Whether your bagged doodle has some data swag on it or not, the bird itself holds a treasure chest filled with specific information. By measuring its bill and wing chord along with distinguishing the characteristics of its primary feathers, a woodcock can be both aged and sexed. Performing these tactics in the field not only enhances your knowledge of woodcock, but it can also contribute to the management of woodcock. Some states encourage hunters to send in the wings of harvested woodcock to be sexed and aged by wildlife professionals. Comparing this data to previous years, weather trends and other factors can help influence harvest regulations and habitat management planning.
Why Research for Quality Habitat Management Matters
The impacts of wildlife research are monumental. Research provides valuable information to wildlife managers and the public through analyzed data. This data plays a large role in habitat management, hunting regulations and public knowledge. Implementing specific management techniques along with strategic planning is vital in sustaining populations of desired wildlife. With all of this, the result is the creation of quality habitat for wildlife.
Tactics for success may involve attempts at controlling invasive species, such as buckthorn or honeysuckle, to promote native, beneficial flora for wildlife. Certain chemicals, application techniques and times of the year may influence your success in diminishing these unwanted woody species. Cost of supplies can be compared with efficiency of the herbicides along with the effects that they’ll have on the environment. Other examples include performing precisely timed and sized cuts of aspen and other tree species to create necessary age class diversity on the landscape. When performing these cuts, strategic manipulations like ensuring that snags, fallen logs and other coarse woody debris will be left as crucial cover and drumming sites for ruffed grouse should be taken into consideration.
Additionally, it can be important to create wildlife openings within these cuts to provide areas for woodcock to perform their sky dances and for grouse and turkey broods to feed on insects that are essential for their rapid body growth. These forest openings are pivotal for countless other bird species and fauna as well. Noncommercial alder shearing promotes vital age class diversity for the American woodcock, golden-winged warbler and many other wildlife species. Size, shape and timing of shearing can affect the quality of habitat. Knowing that certain alder stands might not possess the correct structure to produce a successful end result post shearing is critical along with the timing of the shearing to ensure mechanical operation. All of these strategies, thoughts and considerations have been modified, improved and then implemented thanks to the findings research has gifted us with. Constant trial and error over time will display a pattern to help us act stronger on habitat management. Without research, impactful habitat management isn’t possible.
Purchase “A Woodcock in the Hand” for a more detailed account of how to age and sex American woodcock.
