Osamu Shimomura shared the 2008 Nobel Prize in Chemistry for his research into the green glowing protein in jellyfish, GFP. The protein can be made on a structure of interest and then "lit up" so that the other protein or structure can be easily located under a microscope. It has led to several breakthroughs in Biology and Medical Research.
To do the initial research, Shimomura had to catch 100,000 jellyfish.
Daily Yomiuri reports:
In the state of Washington, where Shimomura was based at the time, there were so many Aequorea victoria jellyfish living in the sea nearby that local residents said they could walk on the water as a result. As his research would require up to 3,000 jellyfish a day, Shimomura, his family members and his assistants would repeatedly scoop up jellyfish using long-shafted nets, depositing them in one of about 30 buckets placed at intervals of five meters along a pier.
It goes on:
Due to a rapid decline in the number of jellyfish over the past 10 years or so, it has become impossible to capture large quantities of them.
Perhaps we also need a Nobel Prize in population dynamics.