January 21, 2024 –A giant tree in your backyard can reveal stories about Earth’s past climate. The concentric rings in the trunk, besides indicating the age of the tree, also shed light on the corresponding weather conditions during each year of the tree’s life.
But growth rings are not exclusive to trees. Similar rings found in the tiny ear bones of fish provide clues about the effects of climate change on both land and sea.
Bryan Black, an associate professor of dendrochronology at the University of Arizona Laboratory of Tree-Ring Research, has been applying the tree-ring dating techniques to so-called “fish rings” to understand how environmental variability is affecting fish growth and productivity over decades.
In this Q&A, Black discusses the techniques he uses to study growth increments in the ear bones, or otoliths, of fish; the correlation between otoliths and climate change; and how the fish-ring dating technique is comparable to tree-ring dating.