Arizona
Getty Images/Mario Tama

A recent study indicated that fish species with more than 100 years of lifespan have been found in Arizona Desert.

Experts have discovered that three or more species have known lifespans that are greater than 100 years.

This could later open the doors to aging studies across disciplines, such as gerontology and senescence or aging among vertebrates.

Buffalofishes

A previous study on buffalofishes have uncovered revelational age-validated life history characteristics from careful examination of the otolith (earstone). First, bigmouth buffalo at 112 years of age was discovered and age-validated to be the longest-lived freshwater teleost, which is a group of more than 12,000 species.

A few years later, individuals as old as 127 years with hatch years in the 1890s were discovered, which nearly quintupled their known maximum age prior to 2019 (26 years). Bigmouth buffalo are one of the longest-lived vertebrates and are a periodic strategist.

Bigmouth buffalo also show negligible senescence and physiological improvements at 100 years old and accrue external black or orange spots with advanced age.

In the latest study, scientists investigated age structure, external pigmentation spots, rod-and-line catchability, recapture dynamics, and population demographics of buffalofishes from Apache Lake, Arizona.

Using the information they had obtained, the experts analyzed recruitment over time, determine whether presence or abundance of spots differs across species, and test if the number of orange spots and black spots are correlated within individuals.

They also compiled buffalofish angling capture events over the past six years from Apache Lake, reported eon the number of recaptures based on unique markings on individual fish, and traced the size fluctuations and movement of individuals.

"With a sample size of only 23 individuals across the three species of buffalofishes at Apache Lake, we found direct evidence of centenarian longevity for black buffalo (108 years), bigmouth buffalo (105 years), and smallmouth buffalo (101 years)," the study indicated.

Age Demographics

Scientists said that a school of fish have provided an excellent opportunity to understand age demographics of wild populations because most species can be aged directly via the thin-sectioned otolith.

Indeed, this technique also allowed for age validation of long-lived species, which has been rigorously demonstrated for buffalofishes.

Prior to 2019, experts said that no buffalofish species was known to live more than 26 years.

Further, they said that in the past four years, buffalofishes have gained substantial study and attention, and as a result, are amidst a paradigm shift in the way we humans understand them.

The bigmouth buffalo has been discovered to exhibit a slow pace of life, pronounced episodic recruitment, negligible senescence, improvements in physiological systems at 100 years old, and a maximum reported longevity of 127 years from the first sample (n = 52 individuals) analyzed from Canada.

The experts said that in Arizona, they found ages that nearly double the previously reported maximum age of 56 years for black buffalo, and increase the maximum longevity known for smallmouth buffalo (62 years) by several decades.

Evidence indicated that individual buffalofishes from the Arizona stocking in 1918 are likely still alive as of 2023.