Mammal Study Merit Badge

Requirement 3 is 15 hours, or 6 hours, or none

The three routes are printed as a plain list. Here is what they actually cost:

3(b) is two and a half times the field time of 3(a) and it fixes the number of days at five. 3(c) needs no field time at all.

None of that is a reason to pick the short one: sitting still in a wood for fifteen hours is how most people who earn this badge remember it. It is a reason to decide before you start rather than after two outings.

4(c) points back at 3(c) by number

Requirement 4(c) asks for a life history of a game mammal, covering the points outlined in requirement 3(c).

So:

• if you chose 3(c) and also choose 4(c), you write two life histories to the same outline: one nongame, one game. It is the only place on this badge where the work doubles.
• if you chose 3(a) or 3(b) and choose 4(c), you still have to read 3(c) (a requirement you are not doing), because that is where the outline is. Neither of those is stated anywhere on the badge.

Requirement 5 is the big one

Working with your counselor, select and carry out one project that will influence the numbers of one or more mammals.

Twenty-two words. No clock, no examples, and working with your counselor means the project is agreed before it begins, not reported afterwards. It is the requirement most likely to still be open when everything else is finished, so raise it at your first meeting rather than your last.

Requirement 6 is about work you have already done

It asks how you have followed the Leave No Trace Seven Principles and the Outdoor Code during field observation, specimen collection, and identification. That is requirement 3, and possibly requirement 4.

You cannot answer it honestly afterwards by remembering harder. Read it before your first outing.

The 25 acres that became 4

The 2025 requirements book asks 3(b) for at least a 25-acre area (about the size of 3½ football fields). The current page asks for at least a 4-acre area (about the size of 3 football fields).

A football field with its end zones is about 1.3 acres, so three of them come to about 4. The page is the version whose two halves agree with each other, and it is the newer one. If you are working from a printed book here, check the page.

What this page is

The Mammal Study merit badge, drawn so both choices and their real costs are visible before you commit to one. It is not a copy of the requirements: each step is a short label with a link to the official requirements, which are what actually governs and which change from year to year.