It’s actually much simpler than it seems. We have two lasers that have been calibrated to 4 inches apart and this is true to about 40ft away. We shoot the fish with the laser at a 90 degree angle and this is coupled with video. So when we go back to analyze the videos we can take screen caps of when the lasers are hitting the fish perfectly and using a measuring software take accurate measurements of the fish
On this fish you can see the 2 dots from the laser. With them being 4 inches apart this giant measured to about 9ft in length making it the largest one ever sized
The best thing you can do is get lab experience, and internships. You could have a degree in biology, microbio, biochem, math, physics, chem, etc. and have an equal chance at getting into a grad school if you have had a good internship/ lab to work in.
With any science major you are able to take marine classes, but it does help to have skills outside of marine biology (e.g. math, computer science, stats) because those skills will set you apart from others who are trying to get into that same program.
Many marine ecologists use a lot of modelling so knowing how to read and write code and knowing bio stats makes you stand out against the rest.
Just have fun with it. Working in marine systems is requires long hours and a lot of patience, both in the field and in the lab. One of my mentors said to me “Science never sleeps, so neither should you.” and it’s totally true. You don’t get to rest until you’re done. Because of this, it is very easy to get wrapped up in all the work and start to hate what you are doing, but if you can just step back and find some time for fun you will be set.
Here are a couple tips that I think you should consider
Goodluck on your endeavor, it’s an amazingly rewarding field to work in. If you do it right, you will get to visit some really awesome places around the world.
"If science were easy, everybody would be doing it" -Pete Edmunds