TY - JOUR
T1 - Trophic variation during the early stages of blacktip sharks (Carcharhinus limbatus) within coastal nurseries of the Galapagos Marine Reserve
AU - Páez-Rosas, Diego
AU - Suarez-Moncada, Jenifer
AU - Elorriaga-Verplancken, Fernando R.
AU - Proaño, Alberto
AU - Arnés-Urgellés, Camila
AU - Salinas-de-León, Pelayo
AU - Galván-Magaña, Felipe
N1 - Publisher Copyright:
© 2021
PY - 2021/4
Y1 - 2021/4
N2 - The blacktip shark (Carcharhinus limbatus) is a placental shark that uses coastal nursery areas in the Galapagos Marine Reserve, where juveniles live during their early life stages. To better understand the feeding behavior of early juvenile blacktip sharks, we conducted stable isotope analysis on 57 samples from three coastal nurseries around the archipelago. We evaluated the intraspecific variation in trophic shifts of four size classes (<60, 60–69, 70–79 and ≥ 80 cm TL) based on δ13C and δ15N signatures. No significant differences in δ13C and δ15N values were observed among nursery areas (P = 0.127 and P = 0.736, respectively) nor between sexes (P = 0.881 and P = 0.993, respectively). However, there were significant differences among size classes, with δ13C and δ15N values showing a negative relationship with size (R = −0.54, P = 0.001 and R = −0.60, P = 0.001, respectively). Neonates (TL < 60 cm) exhibited a larger trophic niche, whereas larger individuals (TL ≥ 80 cm) exhibited a reduction in trophic niche as a result of different use of resources. Clustered δ15N signatures for the two largest size classes showed similar feeding patterns and same trophic level, while δ13C signatures in all size classes showed the use of several primary carbon sources. Our results showed trophic variations among early life stages, as a result of maternal reminiscence in neonates and foraging variation in larger size classes across coastal nursery areas. This is baseline information on the feeding behavior of early juvenile blacktip sharks in the Tropical Eastern Pacific.
AB - The blacktip shark (Carcharhinus limbatus) is a placental shark that uses coastal nursery areas in the Galapagos Marine Reserve, where juveniles live during their early life stages. To better understand the feeding behavior of early juvenile blacktip sharks, we conducted stable isotope analysis on 57 samples from three coastal nurseries around the archipelago. We evaluated the intraspecific variation in trophic shifts of four size classes (<60, 60–69, 70–79 and ≥ 80 cm TL) based on δ13C and δ15N signatures. No significant differences in δ13C and δ15N values were observed among nursery areas (P = 0.127 and P = 0.736, respectively) nor between sexes (P = 0.881 and P = 0.993, respectively). However, there were significant differences among size classes, with δ13C and δ15N values showing a negative relationship with size (R = −0.54, P = 0.001 and R = −0.60, P = 0.001, respectively). Neonates (TL < 60 cm) exhibited a larger trophic niche, whereas larger individuals (TL ≥ 80 cm) exhibited a reduction in trophic niche as a result of different use of resources. Clustered δ15N signatures for the two largest size classes showed similar feeding patterns and same trophic level, while δ13C signatures in all size classes showed the use of several primary carbon sources. Our results showed trophic variations among early life stages, as a result of maternal reminiscence in neonates and foraging variation in larger size classes across coastal nursery areas. This is baseline information on the feeding behavior of early juvenile blacktip sharks in the Tropical Eastern Pacific.
KW - Carcharhinus limbatus
KW - Early juvenile stages
KW - Feeding behavior
KW - Galapagos Marine Reserve
KW - Nursery areas
KW - Stable isotopes
UR - http://www.scopus.com/inward/record.url?scp=85102265126&partnerID=8YFLogxK
U2 - 10.1016/j.seares.2021.102023
DO - 10.1016/j.seares.2021.102023
M3 - Artículo
AN - SCOPUS:85102265126
SN - 1385-1101
VL - 170
JO - Journal of Sea Research
JF - Journal of Sea Research
M1 - 102023
ER -