Factors Affecting Abundance, Growth, and Survival of Age-0 Gizzard Shad

Abstract

Factors affecting abundance, growth, and survival of age-0 gizzard shad Dorosoma cepedianum were examined in Pomme de Terre and Stockton lakes. Missouri, during 1987Missouri, during -1991 Otolith ages were used to assign larvae (^25 mm total length, TL) and juveniles (>25 mm TL) to weekly cohorts so that cohort-specific estimates of abundance, growth, and survival could be made. The distribution of initial abundances of larvae among weekly cohorts was influenced by water temperature and reservoir water level but not by characteristics of adult females (abundance, size, condition, fecundity). Intense periods of spawning activity during rising water levels resulted in high peaks in larval abundance and relatively few large weekly cohorts (e.g., 1990). In the absence of water level rises, peaks in larval abundance were much lower and abundances of larvae were more evenly distributed among several cohorts (e.g., 1988). Spring warming also affected spawning; early cohorts in warm springs (1987 and 1991) were relatively more abundant than those during cool springs (1989 and 1990). The initial distribution of larvae among weekly cohorts influenced subsequent interactions between the larvae and their environment. Growth of larvae was positively affected by water temperature and, to a lesser degree, food abundance. Early cohorts grew slower because of lower water temperatures, and they suffered higher mortality than did late cohorts. Survival was also density dependent; weekly cohorts with high initial densities experienced lower survival than cohorts with small initial densities. High survival of larvae occurred in 1988 when densities of larvae were low and evenly distributed among weekly cohorts and food abundance was high. Growth and instantaneous mortality of juveniles were not closely tied to any single variable. Growth was positively related to food abundance and negatively related to gizzard shad density. Mortality was not significantly related to any measured variable. Overall, findings indicate that cohort dynamics of age-0 gizzard shad are initially driven by climatic factors and later by a combination of climatic and biotic factors.Gizzard shad Dorosoma cepedianum are impor-Despite their importance, factors affecting abuntant prey for many sport fish in reservoir ecosys-dance, growth, and survival of age-0 gizzard shad terns (Noble 1981;Storck 1986; Johnson et al. are not well documented. Initial abundances of lar-1988; Michaletz 1997, this issue), but they are also vae have been related to condition of adult females potentially detrimental competitors of young sport (Stock 1971;Kampa 1984;Willis 1987). Also, fish and other planktivores (Kirk and Davies 1987; i arger females may spawn earlier (Miranda and DeVries and Stein 1992;Welker et al. 1994). Muncy 1988) and over a shorter time (Willis 1987) Age-0 gizzard shad can be especially forceful comthan smaller counterparts, affecting temporal aspetitors because they are more zooplanktivorous pects of |arva , hatching and abun dance. Environthan their older cou...

Linking Landscapes and Food Webs: Effects of Omnivorous Fish and Watersheds on Reservoir Ecosystems

“…Studies in Alabama, Ohio, and Missouri reservoirs, and natural lakes in Florida, reveal that gizzard shad abundance increases strongly with ecosystem productivity, more so than that of other fish species (Bachmann et al 1996, DiCenzo et al 1996, Michaletz 1997, Bremigan and Stein 2001. Gizzard shad are scarce in unproductive (oligotrophic) ecosystems, common in moderately productive (mesotrophic) ecosystems, and very abundant under highly productive (eutrophic and hypereutrophic) conditions.…”

“…may contribute. Growth rate of individual YOY gizzard shad does not clearly correlate with reservoir productivity across mesotrophic to hypereutrophic conditions (DiCenzo et al 1996, Michaletz 1997, although in at least some years, YOY gizzard shad in hypereutrophic reservoirs grow to a larger size than those in eutrophic reservoirs (Bremigan and Stein 1999). Rapid growth may enhance firstyear survival of gizzard shad by decreasing their predation risk to gape-limited piscivores such as bass (predation risk may also be lower in highly productive, turbid reservoirs because of decreased detection by visual predators; see below).…”

Habitat use and preference of adult perch (Perca fluviatilis L.) in a deep reservoir: variations with seasons, water levels and individuals

“…Indeed, WLF can lead to loss of potential prey (Winfield, 2004), loss of refuge areas (Kaczka & Miranda, 2014) and loss of spawning habitats (Hudon et al, 2005) for fish fauna. Finally, WLF may also decrease fish recruitment if WL drops after spawning (Kahl et al, 2008) and fish eggs desiccate (Michaletz, 1997;Winfield, 2004). Therefore, Coops et al (2003) and more recently Tao et al (2016) highlighted the urgency of collecting ecological data on fish-habitat relationship.…”

Larval gizzard shad characteristics in Lake Oahe, South Dakota: a species at the northern edge of its range

“…Gizzard shad are an important prey resource for a suite of sport fishes (Storck 1986;Michaletz 1997Michaletz , 1998 and can strongly influence growth, recruitment, and survival of predatory fishes (DeVries and Stein 1990;Garvey and Stein 1998;Bauer 2002). Predation of gizzard shad by recreational fishes, such as largemouth bass (Micropterus salmoides), walleye (Sander vitreus), white crappie (Pomoxis annularis), and white bass (Morone chrysops), is dependent on the growth of age-0 gizzard shad (Michaletz 1997(Michaletz , 1998. In some systems, gizzard shad produce slow-growing individuals that are vulnerable to fish predation (Storck 1986;Michaletz 1997Michaletz , 1998Allen et al 1999).…”

“…Predation of gizzard shad by recreational fishes, such as largemouth bass (Micropterus salmoides), walleye (Sander vitreus), white crappie (Pomoxis annularis), and white bass (Morone chrysops), is dependent on the growth of age-0 gizzard shad (Michaletz 1997(Michaletz , 1998. In some systems, gizzard shad produce slow-growing individuals that are vulnerable to fish predation (Storck 1986;Michaletz 1997Michaletz , 1998Allen et al 1999). In contrast, in systems where age-0 shad growth rates are high, shad quickly reach sizes that fishes are unable to exploit (Noble 1981).…”