| Abstract: | Otoliths from laboratory-reared northern squawfish, Ptychocheilus oregonensis, larvae were examined to determine the periodicity of increment deposition. Increment deposition began in both sagittae and lapilli after hatching. Reader counts indicated that increment formation was daily in sagittae of 1-29-day-old larvae. However, increment counts from lapilli were significantly less than the known ages of northern squawfish larvae, possibly because some increments were not detectable. Otolith readability and age agreement among readers were greatest for young (<11 days) northern squawfish larvae. This was primarily because a transitional zone of low-contrast material began forming in otoliths of 8-11-day-old larvae and persisted until approximately 20 days after hatching. Formation of the transition zone appeared to coincide with the onset of exogenous feeding and continued through yolk sac absorption. Our results indicate that aging wild-caught northern squawfish larvae using daily otolith increment counts is possible. |
| Genre: | Article |
| ProdID: | 70020780 |
| Citation Author: | Wertheimer, R. H.; Barfoot, C. A. |
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| Citation End Page: | 175 |
| Citation Issue: | 4 |
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| Citation Language: | English |
| Citation Larger Work Title: | California Fish and Game |
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| Citation Number Of Pages: | 6 |
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| Citation Search Results Text: | Validation of daily increments in otoliths of northern squawfish larvae; 1998; Article; Journal; California Fish and Game; Wertheimer, R. H.; Barfoot, C. A. |
| Citation Start Page: | 170 |
| Citation Volume: | 84 |
| Citation Year: | 1998 |
| Type: | citation/reference |
| Text: | Validation of daily increments in otoliths of northern squawfish larvae; 1998; Article; Journal; California Fish and Game; Wertheimer, R. H.; Barfoot, C. A. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Thu, 1 Jan 1998 00:00 -0600 |
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