Food Habits of Large Nektonic Fishes

Trophic Linkages in Delaware Bay and the Adjacent Ocean

Kenneth Able, J. M. Morson, D. A. Fox

Research output: Contribution to journalArticle

Abstract

Fish diets play a critical role in our understanding of aquatic trophic dynamics and are an important component in developing ecosystem-based approaches to fisheries management. Although large nektonic fishes exert top-down predator effects on the food web and typically support viable commercial and recreational fisheries, little is known about the diet of this guild. We evaluated the diets (6327 stomachs) of four nektonic predatory fishes (Pomatomus saltatrix [78–395 mm], Cynoscion regalis [91–520 mm], Morone americana [156–361 mm], and Morone saxatilis [82–785 mm]) in Delaware Bay and in the adjacent ocean. To assess ontogenetic, geographic, and interspecific variation in diets, observations from individual fish stomachs were clustered into species-size class groups, and dietary overlap was estimated using multivariate analyses. A shift in diet composition, as well as diversity, occurred along the estuarine gradient and into the adjacent ocean. Some prey were shared by most predators, including some crustaceans (dominated by Callinectes sapidus, mysids, and Palaemonetes spp.), fundulids (dominated by Fundulus heteroclitus), engraulids (dominated by Anchoa mitchilli), and clupeids (dominated by Brevoortia tyrannus). However, inter- and intra-specific variation in diet was observed as well. In particular, M. americana consumed fewer engraulids and clupeids, and many more and diverse types of invertebrates, while P. saltatrix consumed more clupeids and less invertebrates. The lack of overlap in diet between the four predators evaluated, and between size groups for each predator, supports previous evidence that these groups feed in trophic guilds defined by species and by size within a species. The highly variable diets for these predators suggest high resolution spatial data are necessary in order to quantify their most important prey and their role in coastal ecosystems.

Original languageEnglish (US)
Pages (from-to)866-883
Number of pages18
JournalEstuaries and Coasts
Volume41
Issue number3
DOIs
StatePublished - May 1 2018

Fingerprint

oceans
diet
food
ocean
fish
predator
predators
Morone americana
Pomatomus saltatrix
guild
stomach
invertebrate
invertebrates
Brevoortia tyrannus
Palaemonetes
Malacostraca
dietary overlap
Fundulus heteroclitus
Callinectes sapidus
Morone saxatilis

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Aquatic Science
  • Ecology

Cite this

@article{bb56d76ee0fc413f99cee989685e7aa5,
title = "Food Habits of Large Nektonic Fishes: Trophic Linkages in Delaware Bay and the Adjacent Ocean",
abstract = "Fish diets play a critical role in our understanding of aquatic trophic dynamics and are an important component in developing ecosystem-based approaches to fisheries management. Although large nektonic fishes exert top-down predator effects on the food web and typically support viable commercial and recreational fisheries, little is known about the diet of this guild. We evaluated the diets (6327 stomachs) of four nektonic predatory fishes (Pomatomus saltatrix [78–395 mm], Cynoscion regalis [91–520 mm], Morone americana [156–361 mm], and Morone saxatilis [82–785 mm]) in Delaware Bay and in the adjacent ocean. To assess ontogenetic, geographic, and interspecific variation in diets, observations from individual fish stomachs were clustered into species-size class groups, and dietary overlap was estimated using multivariate analyses. A shift in diet composition, as well as diversity, occurred along the estuarine gradient and into the adjacent ocean. Some prey were shared by most predators, including some crustaceans (dominated by Callinectes sapidus, mysids, and Palaemonetes spp.), fundulids (dominated by Fundulus heteroclitus), engraulids (dominated by Anchoa mitchilli), and clupeids (dominated by Brevoortia tyrannus). However, inter- and intra-specific variation in diet was observed as well. In particular, M. americana consumed fewer engraulids and clupeids, and many more and diverse types of invertebrates, while P. saltatrix consumed more clupeids and less invertebrates. The lack of overlap in diet between the four predators evaluated, and between size groups for each predator, supports previous evidence that these groups feed in trophic guilds defined by species and by size within a species. The highly variable diets for these predators suggest high resolution spatial data are necessary in order to quantify their most important prey and their role in coastal ecosystems.",
author = "Kenneth Able and Morson, {J. M.} and Fox, {D. A.}",
year = "2018",
month = "5",
day = "1",
doi = "https://doi.org/10.1007/s12237-017-0308-0",
language = "English (US)",
volume = "41",
pages = "866--883",
journal = "Estuaries",
issn = "0160-8347",
publisher = "Estuarine Research Federation",
number = "3",

}

Food Habits of Large Nektonic Fishes : Trophic Linkages in Delaware Bay and the Adjacent Ocean. / Able, Kenneth; Morson, J. M.; Fox, D. A.

In: Estuaries and Coasts, Vol. 41, No. 3, 01.05.2018, p. 866-883.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Food Habits of Large Nektonic Fishes

T2 - Trophic Linkages in Delaware Bay and the Adjacent Ocean

AU - Able, Kenneth

AU - Morson, J. M.

AU - Fox, D. A.

PY - 2018/5/1

Y1 - 2018/5/1

N2 - Fish diets play a critical role in our understanding of aquatic trophic dynamics and are an important component in developing ecosystem-based approaches to fisheries management. Although large nektonic fishes exert top-down predator effects on the food web and typically support viable commercial and recreational fisheries, little is known about the diet of this guild. We evaluated the diets (6327 stomachs) of four nektonic predatory fishes (Pomatomus saltatrix [78–395 mm], Cynoscion regalis [91–520 mm], Morone americana [156–361 mm], and Morone saxatilis [82–785 mm]) in Delaware Bay and in the adjacent ocean. To assess ontogenetic, geographic, and interspecific variation in diets, observations from individual fish stomachs were clustered into species-size class groups, and dietary overlap was estimated using multivariate analyses. A shift in diet composition, as well as diversity, occurred along the estuarine gradient and into the adjacent ocean. Some prey were shared by most predators, including some crustaceans (dominated by Callinectes sapidus, mysids, and Palaemonetes spp.), fundulids (dominated by Fundulus heteroclitus), engraulids (dominated by Anchoa mitchilli), and clupeids (dominated by Brevoortia tyrannus). However, inter- and intra-specific variation in diet was observed as well. In particular, M. americana consumed fewer engraulids and clupeids, and many more and diverse types of invertebrates, while P. saltatrix consumed more clupeids and less invertebrates. The lack of overlap in diet between the four predators evaluated, and between size groups for each predator, supports previous evidence that these groups feed in trophic guilds defined by species and by size within a species. The highly variable diets for these predators suggest high resolution spatial data are necessary in order to quantify their most important prey and their role in coastal ecosystems.

AB - Fish diets play a critical role in our understanding of aquatic trophic dynamics and are an important component in developing ecosystem-based approaches to fisheries management. Although large nektonic fishes exert top-down predator effects on the food web and typically support viable commercial and recreational fisheries, little is known about the diet of this guild. We evaluated the diets (6327 stomachs) of four nektonic predatory fishes (Pomatomus saltatrix [78–395 mm], Cynoscion regalis [91–520 mm], Morone americana [156–361 mm], and Morone saxatilis [82–785 mm]) in Delaware Bay and in the adjacent ocean. To assess ontogenetic, geographic, and interspecific variation in diets, observations from individual fish stomachs were clustered into species-size class groups, and dietary overlap was estimated using multivariate analyses. A shift in diet composition, as well as diversity, occurred along the estuarine gradient and into the adjacent ocean. Some prey were shared by most predators, including some crustaceans (dominated by Callinectes sapidus, mysids, and Palaemonetes spp.), fundulids (dominated by Fundulus heteroclitus), engraulids (dominated by Anchoa mitchilli), and clupeids (dominated by Brevoortia tyrannus). However, inter- and intra-specific variation in diet was observed as well. In particular, M. americana consumed fewer engraulids and clupeids, and many more and diverse types of invertebrates, while P. saltatrix consumed more clupeids and less invertebrates. The lack of overlap in diet between the four predators evaluated, and between size groups for each predator, supports previous evidence that these groups feed in trophic guilds defined by species and by size within a species. The highly variable diets for these predators suggest high resolution spatial data are necessary in order to quantify their most important prey and their role in coastal ecosystems.

UR - http://www.scopus.com/inward/record.url?scp=85028758524&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85028758524&partnerID=8YFLogxK

U2 - https://doi.org/10.1007/s12237-017-0308-0

DO - https://doi.org/10.1007/s12237-017-0308-0

M3 - Article

VL - 41

SP - 866

EP - 883

JO - Estuaries

JF - Estuaries

SN - 0160-8347

IS - 3

ER -