Data from Rapidly increasing methyl mercury in endangered Ivory Gull (Pagophila eburnea) feathers over a 130-year record

Specimen collection data, stable isotope values (δ13C, δ15N), total and methyl mercury concentrations, and museum catalogue numbers.  Data to accompany Bond, AL, Hobson, KA, and Branfireun, BA. 2015 Rapidly increasing methyl mercury in endangered Ivory Gull (Pagophila eburnea) feathers over a 130-year record. Proceedings of the Royal Society of London B Biological Sciences 282: 20150032