What is a Control Sheet?
- A Control Sheet (clink link to see an example and also see example below) is a
vital part of your Tree Swallow project.
- Control Sheets provide control, structure and organization by displaying crucial
information about nests that allow you to see when each box should be
checked and when it must not be disturbed.
- Control Sheets present basic nesting data for each nest that can be used in
making comparisons and when compiling Season Summaries.
How do you use a Control Sheet?
- Control Sheets are data grids with headings at the top. They are more complex
than the other record sheets and may require practice to use, but you'll come
to see how handy and important they are. Examine the fields one by one.
Control Sheet data fields:
- Box #: A list of the numbers of every box in your project. Each box will have
its own series of spaces for numerical data entry spread horizontally across the
- Egg Date: There is a space for the date the first egg was laid and another
space for the date of the last egg. Tree Swallows lay one egg per day, never
more than one, so even if you make infrequent box checks you should be able
to count backward and forward to determine first and last egg dates. It's
especially important to know the last egg date because it helps pinpoint the
date when hatching will occur.
- Clutch #: The total number of eggs laid by the female for this clutch.
- Egg #: The total number of eggs present on the last box check before
hatching. This may be different than clutch # because eggs sometimes are
removed by nest competitors.
- Last Egg Plus 3 6 9 12: These are the calendar dates counting by threes from
the date the last egg was laid. The female is incubating during this time and
box checks need not be made at this box more often than every three days.
Since Tree Swallow incubation lasts about 14 days you should try to check for
hatching soon after day 12. The dates can be crossed out lightly by pencil after
- Hatch Date: The date you believe or know the majority of young in a nest
hatch. Many people use the date the first egg hatched as their official hatch
date. If you aren't able to check a box at the anticipated hatch time count 14
days from the date the last egg was laid and enter that as the hatch date.
- Brood #: The number of young known to hatch. This is often less than the egg
clutch number because not all eggs in every nest hatch.
- Hatch Date Plus 3 6 9 12: These are the calendar dates counting by threes
from the hatch date. Adults are feeding nestlings now, and box checks need
not be made at this box more often than every three days. Knowing these
dates is very important for three reasons. The best time to trap and band
adults is between hatching and day 6. Nestlings should be banded at day 11 or
12, no sooner and no later. And perhaps most important, knowing hatch date
plus 12 lets you see when box checks at this box must stop. The dates can be
crossed out lightly in pencil after they've passed.
- Brood # D 12: The number of young alive at the day 12 box check, or on the
closest day before day 12.
- Fledge #: The number of nestlings that appear to have left the box alive,
determined by subtracting the number of dead young found in the nest after
fledging is complete from the brood number counted on day 12.
- Totals: Egg #, Brood # at hatch, Brood # at D 12, and Fledge # can be totaled
and written under their respective columns (see example 3).
Note that in the example above the numbers were filled in as they either occurred or
could be determined. As the egg and hatch dates plus 3, 6, 9 and 12 passed, each
box was X'ed over lightly in pencil. This makes it easier to see at a glance which
boxes should be checked and when.
Learn About Birds at Tree Swallow Nest Box Projects