ABSTRACT
Coral reef gobies typically invest in somatic growth throughout much or all of their lifespan, spending relatively little or no time at asymptotic size (e.g. Hernaman and Munday, 2005a; see also Fig. 4.2.6). Rapid nearlinear growth has also been recorded in some species, including Istigobius decoratus (Kritzer, 2002), I. goldmanni (Hernaman and Munday, 2005a), Trimma nasa (Winterbottom and Southcott, 2008), and three species of Eviota (Depczynski and Bellwood, 2006). Similarly, the intertidal Hawaiian goby, Bathygobius coalitus, exhibited a linear pattern of growth for at least the fi rst nine months of life, with no diff erence in growth rate between immature and mature gobies (Shafer, 1998). Th e growth pattern of most coral reef gobies diff ers considerably to that exhibited by other relatively small, but long-lived coral reef fi shes, such as certain acanthurids (e.g. Choat and Axe, 1996; Hart and Russ, 1996) and pomacentrids (e.g. Meekan et al., 2001). These long-lived species often have a growth pattern characterized by rapid growth to asymptotic size and sexual maturity, followed by a relatively long period of reproductive activity but little additional somatic growth (Choat and Robertson, 2002). Th is growth pattern may refl ect a physiological trade-off between growth and reproduction. Trade-off s play a central role in life history theory, and a physiological trade-off between growth and reproduction is expected where these two processes compete directly for a limited amount of energy (Begon and Mortimer, 1981; Partridge and Harvey, 1988; Stearns, 1992). Coral reef gobies are apparently able to acquire suffi cient energy to satisfy demands for both growth and reproduction, with no apparent trade-off between these traits. However, this capacity to continue somatic growth throughout life may come at a cost of reduced longevity, possible due to increased exposure to predators while feeding to maintain suffi cient energy to support rapid growth and high reproductive eff ort.
