Attending this event?
Welcome to the interactive web schedule for the 2019 Midwest Fish & Wildlife Conference! The schedule is subject to change (as of November 20, 2018). Please check back for updates. To return to the main Conference website, go to: www.midwestfw.org.

The conference schedule is hosted in SCHED which allows you to search within the schedule, and filter the schedule to show items only occurring on a certain date or within a track/symposia.
  • To view only a certain type of presentation or track, locate the heading "Filter By Type" in the navigation bar. As an example, try clicking on "T01: Fisheries: Great Lakes I".
  • The default view for the schedule is "Simple" which only shows the start time and title of the agenda item. Hover over the button that says "Schedule" to see the different view options. The "Expanded" option will show start and end times, room location, and session description, if there is one.
  • You can build your own schedule by creating a free account with SCHED by selecting "SIGN UP." Watch the "how-to" video to learn more about using Sched. 
  • PLEASE NOTE: Adding agenda items to your schedule through this app does not sign you up for a session. If an agenda item says "pre-registration required" or charges an additional fee, you need to add the item to your registration through the online registration system

View analytic
Tuesday, January 29 • 6:00pm - 9:00pm
(P38) Validating Daily Otolith Increment Deposition in Aquarium-Reared Juvenile Walleye, Sander Vitreus

Sign up or log in to save this to your schedule and see who's attending!

AUTHORS. Kaitlin Ulin, L. Zoe Almeida – Ohio State University; Taylor A. Brown, Cornell University; David Dippold, Stuart A. Ludsin, Elizabeth A. Marshall – Ohio State University

ABSTRACT. The daily age and growth rate of a juvenile fish can provide useful information about early life conditions. Researchers frequently take advantage of the fact that fish otoliths accrue daily rings, which can be counted and measured, to estimate ages and growth rates.  Previous studies have indicated, however, that aging juvenile walleye, Sander vitreus, with otolith increments past 42 d is difficult, if not impossible. This difficulty is partially due to the development of accessory primordia (a second growth plane on the otolith), a problem exacerbated by otolith preparation techniques that obscure rings on different planes. Herein, we examined the accuracy of aging walleye before and past 42 d using known-age, aquarium-reared walleye and a modified otolith preparation technique. Our otolith preparation technique involved gently grinding the convex side of the otolith in three planes: the core, the middle, and the edge. By grinding on the convex side, we removed material along a curved axis to allow visibility of rings from the hatch-check to the most recently laid ring and, therefore, allowed us to age the fish from hatch to capture. Walleye were hatched on April 20, 2018 (± 3 d) and reared for 96 d; sagittal otoliths were collected on days 10, 41, 56, 79, and 96 post-hatch. Otoliths were aged by three readers. We are comparing reader estimates of ages to known ages and analyzing among- and within-reader error to determine if error lies within readers’ interpretation of rings, or if accessory primordia inhibit clear interpretation of daily rings past 42 d. Future experiments manipulating temperature will be conducted to confirm if our findings are consistent under different environmental conditions known to affect otolith growth patterns.

Tuesday January 29, 2019 6:00pm - 9:00pm
Superior Ballroom CD