ABSTRACT
Accurate and reliable age estimates of sharks are important for informing management that will achieve sustainable outcomes for populations. Age is the foundation of many of the essential parameters, such as growth rate and productivity, that are used in demographic analyses and sheries assessments (Cailliet et al., 2006; Campana, 2001). Here, “sharks” is used as a general term to refer to sharks, rays, and chimaeras, otherwise known
as chondrichthyans. Traditionally, to estimate age in sharks, growth bands are counted in their hard parts. Vertebrae or dorsal n spines are primarily used, although caudal thorns have also been found suitable for ageing in a few species of skates (Cailliet, 2015; Goldman et al., 2012; Serra-Pereira et al., 2008). As sharks age, calcied material accumulates in these structures and can produce visible band pairs that, when formation periodicity has been validated, enable age determination (Goldman et al., 2012; see also Chapter 10 in this volume).
