NOAA Teacher at Sea
Aboard Oscar Dyson
August 21 – September 2, 2017
Mission: Juvenile Pollock Fishery Survey
Geographic area of cruise: Western Gulf of Alaska
Date: September 1, 2017
Weather Data: 12 C, sunny
Latitude: 57 40.9 N, Longitude: 151 37.2 W
Science and Technology Log
In addition to NOAA’s juvenile walleye pollock survey, this leg of voyage is also hosting a seabird survey. The United States Fish and Wildlife Service (USFWS) sent a scientist aboard Oscar Dyson to identify and record bird species as the boat travels from one sampling station to the next. To do this, a bird observation station has been set up on the port side (left hand side) of the bridge. This is a good spot to get a clear view of the water and sky ahead of the boat and to the port side.
Not every bird that is seen from the bridge is included. There are some guidelines that must be followed in order to collect data that has scientific validity. One of the major guidelines is that the ship should be moving at a consistent speed for each of the observation periods. If a scientist were to observe birds at a slower speed, he or she might end up recording more species because there is more time to look for and identify then. If a scientist were to observe birds at a faster speed, he or she might end up recording fewer species because there is less time to look for them and identify them.
It is difficult to correctly identify birds at a distance further than 300 meters away. It is also much more likely that a bird will be identified correctly if it closer than if it is further away. In order to account for differences in how accurately a bird can be identified, scientists have set up a system to put the data collected into different categories. First of all, only birds that are 300 meters away or closer are counted and identified. Birds that are seen between 0 – 50 meters away are considered in “Bin 1” and can be identified with the most accuracy. Bin 2 is 50 – 100 meters away, Bin 3 is 100 – 200 meters away, and Bin 4 is 200 -300 meters away. The further away a bird is, the greater the chance that it will not be identified correctly or missed altogether.
Some of the common birds seen on this survey in the Gulf of Alaska include northern fulmars, auklets, shearwaters, black-footed albatross, tufted and horned puffins, storm petrels, kittiwakes, and common murres. Some of these birds, like the fulmars and albatross like to hang around the boat and look for an easy meal from the fishing net. This can make it difficult to avoid counting the same bird more than once. Adjustments are made by the scientist to prevent an overestimation in the number of birds recorded.
We have also seen some very unexpected bird species. There was a trio of peregrine falcons that landed on the ship and traveled with us for a day. Some of the crew on the bridge saw one of them catch a smaller bird and fly off with it! There was also a masked booby that spent a few hours cruising along with us. Masked boobies are native to the waters much further south and have never been seen in the Gulf of Alaska!
Other data about the weather conditions are automatically recorded with the help of a computer. Air temperature, water temperature, wind speed, and wind direction are recorded at the start of each observation session. A GPS device also records the latitude and longitude of the ship every few seconds. All this information helps scientists get a better understanding of which birds were present at different times of year and how weather conditions may affect where they go.
This is the last day of the survey and it is finally sunny! It has been an interesting two weeks for me. It was full of observing new animals and gaining a new understanding of how marine science is conducted. It has also been a great opportunity to meet some very interesting people passionate about their work.
Did you know?
Flatfish have one eye that migrates, or moves, from one side of their head to the other! This happens within the first few months after they hatch. The result is that both of their eyes end up on the same side of their head. This allows flatfish to swim along the bottom of the ocean floor while keeping both eyes facing upward to look for food and to spot predators.