Deer Surveys | Deer Hunting & Management

Conducting Aerial Surveys for White-tailed Deer

Aircraft, including both helicopter and airplanes, can be effectively used to obtain deer density, sex ratios, fawn survival, and deer distribution information in some portions of the US. Although more expensive to conduct than the spotlight and mobile deer surveys, the aerial survey does provide the necessary population data in a short time frame. This information can be utilized to provide harvest recommendations for the entire ranch, as well as individual pastures. So, does a helicopter survey make sense for your deer management program?

The helicopter survey is considered by some to be the most accurate census for determining populations on a given unit of land. However, the total number of deer recorded on helicopter surveys should not be considered a complete count of all deer. Studies indicate that accuracy of helicopter surveys in South Texas brushland is fairly consistent, but they can underestimate deer density by 60-70%!

As a result, the information gathered from this type of survey should be used only as population trend information and for the preparation of annual harvest recommendations with the understanding that the deer density figures are probably conservative.

Helicopter Surveys

For aerial surveys using a helicopter, surveys should start approximately 15 to 30 minutes after sunrise. On ranches with dense vegetation and/or hills, it is recommended to start at least an hour or more after sunrise due to shadows. Of course, the drawback to starting later is that deer movement is reduced — so you need to keep some of these factors in mind and make sure that survey techniques are consistent over time. Continue reading “Conducting Aerial Surveys for White-tailed Deer”

Using Game Cameras to Survey White-tailed Deer

Population estimation of white-tailed deer is an important cornerstone for the development of deer management strategies. However, estimating deer populations in heavily forested regions is difficult because of reduced visibility. Traditional survey methods, including spotlight counts and aerial surveys, provide limited results in dense forests. So now what?

The use of game cameras, or trail cameras, can provide photo records of an individual deer, a deer herd, and important parameters such as population estimates, sex ratios, and productivity. In an attempt to estimate a deer herd using game cameras, a census project was carried out in 2004 in the piney woods of east Texas, on a property 1,002-acres in size. A total of 7 cameras were placed out (1 trail camera per 150-acres) from September 2 to September 12.

A total of 158 photographs of deer were taken during that time. Twenty-three buck, 97 doe, and 48 fawn photos were collected/observed. Of the 23 total buck observations, 15 individual bucks were identified. The buck to doe ratio was calculated to be 1 buck:4.2 does (23 bucks:97 does). Since 15 individual buck photos were taken, 15 was multiplied by 4.2 to give a doe population size of 63 animals. Continue reading “Using Game Cameras to Survey White-tailed Deer”

Pros and Cons of Aerial Surveys for Deer

Estimating the number of deer on your property is premium information for any deer manager. However, regardless of the type of census survey you use, some type of bias does exist. With this in mind, all surveys provide population trend data and some provide more precise data than others.

Today, we are going to talk about some of the pros and cons of performing aerial surveys for deer. In most cases when conducting aerial surveys for deer, helicopter will be used over airplanes (fixed-wing). With that said, helicopter and fixed-wing surveys allow the landowner and deer manager to determine the following: Continue reading “Pros and Cons of Aerial Surveys for Deer”

Daylight Observation Surveys to Determine Deer Herd Composition

Daylight observations are an ideal way to survey a white-tailed deer herd to determine the herd composition (sex ratios), reproductive success (% fawn crop), and the body condition of deer in a given area. Collecting daylight observations is an easy way to survey the deer herd on your property and data are easy to collect, often incidentally to other activities. Data collected during daylight observations should include sex (buck or doe), age (adult or fawn), and antler quality (number of points, spread, and anything else you can ascertain).

The best time to conduct daylight observation surveys is towards the end of summer and into early fall. In general from mid-August to mid-September is ideal because bucks have identifiable antlers, does are active and moving readily, and the majority of the fawn crop should be old enough to be active, be seen, and be recorded. In addition, this is a great time to collect daylight data because most hunters and land managers are out getting geared up for the upcoming hunting season. All you have to do is work up a data sheet or carry a notepad, carry a trusty set of binoculars and/or a spotting scope, and record animals observed while in the field. Continue reading “Daylight Observation Surveys to Determine Deer Herd Composition”

Deer Surveys and Harvest Strategy

Long-term planning is feasible in deer management, but different years can call for slight to moderate changes in annual harvests based on habitat conditions, fawn survival, and estimated population numbers. Without conducting a deer population survey to get a good estimate of your overall deer numbers and density, you are literally shooting into the wind. Although deer surveys are simply "good estimates" when properly performed, they will keep you on the right track with regards to your long-term management.

Let's take a look at how annual changes in fawn survival can impact your annual harvests. For example, let’s assume you have a long-term goal of 100 deer on your property, the property is at carrying capacity (100 deer), and you have a 1:1 buck to doe ratio. If your late summer/early fall fawn crop is estimated at 50% (25 fawns from 50 does) then you need to remove 25 deer this fall.

However, if you have an 80% fawn crop next year, that is a total of 40 animals you have to remove from the deer herd to keep the population at carrying capacity. Although your long-term population goal stays the same, your annual harvests will fluctuate to some extent. This is an adaptive harvest strategy allows you to keep number in line with carrying capacity and stay on track. As you can see, getting annual estimates of the deer population as a whole, and particularly fawn survival, is important for the proper management of your deer herd.