3.1. Effort-based 10-minute transect counts

Counts of species are of no use unless there is a context to those numbers. For example, ten birds counted in 1 minute says something very different to 10 birds counted in 1 hour. Similarly, 10 birds seen in 10 minutes in a small area is different to 10 birds seen in 10 minutes in an area 10-times the size. For counts to be useful, we need to know the effort that went into the counting. Effort is the time spent counting, and the area of the sea around the boat that was included in the count. It is as important to record these accurately as it is to do the actual counts. Without effort recorded accurately, the counts are useless. Regardless of whether you count up to 300m or up to 100m if its foggy, or whether you count for a full 10 minutes or if your transect is cut short to 4 minutes because the vessel stopped RECORD IT. From that, regardless of the unit used we can calculate the density of birds, distribution patterns and an index of abundance.

Rules for effort-based transects

• ALWAYS COUNT FROM THE BOW (FRONT) of the vessel or an elevated point and looking forwards.
• ONLY COUNT WHEN THE VESSEL IS MOVING AND IN A CONSISTENT DIRECTION
• DO NOT COUNT SHIP FOLLOWERS. This includes birds that come in from outside the count area during the count, specifically to investigate the boat. Many birds will also circle or do zigzags around a boat, making it very difficult to know what to do. If in doubt, leave it out.
• ALL SPECIES ARE EQUAL. Aside from ship-followers, it is crucial to count every single species – do not focus only on rare or “exciting” birds or birds that are bigger and easier to see. All birds are equally important to record.
• ALWAYS KEEP COUNTING EVEN WHEN THERE ARE NO BIRDS (i.e. count = 0). Knowing that a certain patch of ocean had no birds in it is very useful.
• COUNT BIRDS THAT ARE FLYING VS. SETTLED ON THE WATER SEPARATELY. Moving birds cover big areas – termed 'flux' – and are thus more likely to enter the count area than birds that are sitting still. Treating them the same will introduce a bias towards birds that are flying. An easy way to differentiate during counts is to circle tallies of sitting birds in your counting notes.
• ALWAYS RECORD TIME AS SHIP TIME. On some cruises vessels may switch time zones, always keep time according to the ship time. This would mean that all bird counts are relative to environmental times (e.g. sunrise) no matter which time zone is encountered.

How to do an effort- based transect count:

1. For each count, record date, start time, end time, start position and end position off your GPS. Make sure your GPS is set to record in decimal degrees. A 10 minute transect is preferred however if your transect is cut short for some reason (e.g. boat stops suddenly) that is okay, just record the time spent counting. Do not record for longer than 10 minutes.
2. Define the distance from the boat that you are counting – typically 0-300 m. This too can vary between counts (e.g. 0-50 m or 0-200 m) usually due to visibility, but again, record what you are doing for each count. Much further than 300 m and small species cannot be reliably identified and are very likely to go unnoticed, which would bias counts against smaller, less visible species. Therefore 300 m is the maximum distance from the ship we record.
3. Decide on the arc (90° or 180°) from the bow that will be counted. This can vary between counts, as long as you record what you are doing for each count). Why would this change? If a low sun or strong reflections makes counting to one side difficult, or there is a sail or bulkhead or some other obstruction, or you are on your own with lots of birds around, count only to one side (90°).
4. Count the number of each species seen remembering to record these as either flying or sitting. You can use shorthands or keys for spp, e.g. BBA for Black-browed Albatross)

3.2 Snapshot counts

A handful of snapshot counts off the stern (back) of the boat during the day are helpful to get an idea of which birds are around or are following the ship. Obviously counting ship followers here is okay. But just make sure to note in the excel spreadsheet the type of transect as “snapshot” and that ship followers were included.

1. Record the time and GPS position. The start and end times and GPS points will be the same for a snapshot count, even though you will have moved a bit
2. Decide on the count area (count distance and arc) and record this.
3. Count each species, in turn, within the count area in a single moment in time (“a snapshot”). Don't wait for lots of birds before doing the count, just go through the species as fast as you can, one- or a couple of species at a time.