Record Details
Field | Value |
---|---|
Title | The feeding habits of three species of lantern-fishes (Myctophidae) off central Oregon |
Names |
Tyler, Harry Raymond, Jr.
(creator) Pearcy, William G. (advisor) |
Date Issued | 1970-01-27 (iso8601) |
Note | Graduation date: 1970 |
Abstract | The feeding habits of the lanternfishes Tarletonbeania crenularis, Diaphus theta and Stenobrachius leucopsarus were studied by analyzing 1,735 stomachs from 54 collections from the slope waters off Newport, Oregon. Forty-one taxa of food items were identified. Euphausiids (Euphausia pacifica), copepods (Calanus spp. and Metridia lucens) and amphipods (Parathemisto pacifica) were most common. Copepods were numerically most abundant, but euphausiids made up most of the biomass and accounted for the majority of the identifiable food in 41% of the T. crenularis, 40% of the D. theta and 49% of the S. leucopsarus. No large differences in the feeding habits were correlated with size of individuals of the three species of lanternfishes. Some small fishes contained more copepods than euphausiids, but even so, total euphausiid biomass was usually greater than copepod biomass. Empty stomachs were found in 1% of the D. theta, 20% of the T. crenularis and 24% of the S. leucopsarus collected at night. Limited data suggested that during the winter the fishes from 25 miles offshore ingested larger numbers of euphausiids than copepods, while fishes 45 miles offshore fed more on copepods than euphausiids. Changes in stomach fullness during the night, morning and afternoon indicated that most of the lanternfishes fed primarily at night in the upper 200 meters, with some morning and perhaps some afternoon feeding. Comparisons of stomach contents with catches of plankton nets suggested that euphausiids, copepods and amphipods were selected as prey over medusae, shrimps and fishes. |
Genre | Thesis/Dissertation |
Topic | Lantern-fishes |
Identifier | http://hdl.handle.net/1957/22947 |