Maine Deer Spy

two deer in forest

Do you enjoy watching deer? Do you want to help Maine’s biologists better understand the white-tailed deer population? Become a citizen scientist for the Maine Deer Spy project! Volunteers are needed across the state and everyone can participate.


For wildlife biologists, regulated harvest of antlerless deer is the primary means of controlling deer populations at a healthy level. Since 1986, Maine Department of Inland Fisheries and Wildlife (MDIFW) has used the Any-deer Permit (ADP) system to regulate the number of antlerless deer harvested. When determining the number of ADP to issue each year, it is important to estimate recruitment rates (how many fawns each doe is able to raise up until the hunting season) so we can account for how many deer are added into the population each year and what proportion of the doe population we can lose while keeping the population healthy and stable. Since the ADP system was devised, we have relied on lactation rate and embryo rate data, which has allowed us to estimate the proportion of does that successfully reared fawns and the number of fawns produced by each doe. These data are collected primarily during the regular firearms season when biologists examine thousands of deer and collect data on physiological condition and reproductive status; however, because there is little antlerless harvest in much of the state and few female deer to examine and because lactation data are difficult to reliably collect, our knowledge of recruitment is limited in many areas.

To bolster our understanding of whitetail recruitment patterns in the state, we’ve created a citizen science project to solicit help from Maine’s citizen scientists. This project, Maine Deer Spy, allows deer and wildlife enthusiasts as well as Department staff around the state to record and report their deer sightings in a way that feeds right back into Maine’s deer management. The data that we receive will be used as a secondary source of recruitment data and to increase confidence in our understanding of whitetail recruitment patterns throughout Maine.

For 2021, we have added a data field for “Habitat Type.” A PhD student from the University of Maine's Ecology and Environmental Science program and National Science Foundation's Research Traineeship in One Health and the Environment is interested in citizen science observations of deer by habitat types, in particular she is interested in overlap with people, pets, and livestock, such as in agricultural and residential areas. These data may support current and future research efforts in the areas of agricultural crop damage, parasite spread, and tick-borne diseases or disease spillover.

How to Participate

Participating is easy! When you see deer between August 1 and September 30, all you need to do is make simple observations and submit them. For 2021, which will be the second year of this project, there will be two options for submitting data:

Option 1- Postal Mail Data Submission

If you wish to participate in Maine Deer Spy and submit observations by postal mail, please print the data recording form and instructions (PDF) and return completed data forms by October 15, 2021. Please return completed data sheets to:

ATTN: Nathan Bieber, Maine Deer Spy
Maine Dept. of Inland Fisheries and Wildlife
106 Hogan Road, Suite 1
Bangor, ME 04401

Option 2- Online Data Submission

You may enter each observation that you make online at the link below. This link will open the online data entry tool in your browser.

2021- Deer Spy- Online Data Submission

For examples of how to correctly report your observations, please view this short guide (PDF)

Progress and Future

Last year, 2020, was the first year of data collection for the Maine Deer Spy project. Data were collected from July 20th to September 10th, and 3,076 observations were collected from 605 different observers. Among lone does, which offered the highest confidence observations, 47.8% of observed does had fawns with them and 52.2% did not. Among does statewide with fawns, each doe had an average of 1.49 fawns alongside.

We will review the data received to determine whether this project can meet our data collection needs, and we will consider enhancing online data collection options in the future.

Data from this project will also be summarized each year in the MDIFW Research and Management Report.

Frequently Asked Questions

I’d like to participate. Do I need to register anywhere or sign up?

No, anyone who wishes to participate can do so without registering or signing up.

Can I count deer in my yard?

Yes, please do. If possible, avoid counting the same deer on multiple occasions.

How should I report a deer that I see many times? How do I avoid counting deer multiple times?

If you suspect you’re looking at a deer that you’ve already counted, then do not count it again. There are some things we can do after data collection is complete to remove some likely duplicates, but there is no way to remove them all. It won’t be possible for people to always tell deer apart. Do your best!

How do I document large groups of deer?

Try to view the group for long enough to get a rough idea of group relationships. The data reporting form will ask you to break down your observation in an intuitive way making note of does that are with fawns, does that are without fawns, etc. If you frequently view large groups of deer in one location, only submit data for the area once.

For examples of how to correctly report your observations, please view this short guide (PDF)

How can I tell the buck fawns apart from the doe fawns?

For this project, you can record all fawns the same as just “fawns.” It would be very difficult to tell a buck fawn from a doe fawn this time of the year.

What Wildlife Management District (WMD) is my town in?

If you are unsure, use the interactive WMD map or download and print a PDF description or map.

Why can’t I submit sightings from my trail cameras?

Trail cameras can provide a lot of very useful information, but because their viewing window is relatively small, it’s difficult or impossible to account for animals that may be present on the other side of the camera or just out of view of the camera. For example, a trail camera photo of a lone doe may be missing another deer that passed on the other side of the camera or was lagging behind, whereas a direct observation would likely account for the other deer.

Why can’t I send in data from before the start date?

We want to estimate how many fawns are being recruited into the pre-hunt population. Because many fawns don’t make it through their first few weeks of life, we want to start observations a bit later when most fawns are at least six or seven weeks old. At this age, they are very mobile and more likely to survive until the hunting seasons begin and the population structure changes.