Showing posts with label Virginia Tech. Show all posts
Showing posts with label Virginia Tech. Show all posts

Wednesday, November 18, 2015

On the Life of Kelly J. Meyer, by Don Orth

On October 24th I posted birthday wishes to Kelly Meyer on Facebook.  I sent him a photo of a Brook Trout for his birthday wishes. It was my last communication with him.   On the evening of November 4th, he died unexpectedly (see obituary), and, as is typical, I grasped for words to comfort his wife, Denise, and sons, Jack and Andrew, who I never knew, never met.  No words would come, only sadness.   Kelly was one of my graduate students from 1988 to 1990.  His life (vita from this 1990 MS thesis appears below) during his years at Virginia Tech remain among my fond, faded memories.  
During his time as a graduate student, Kelly studied the bioenergetics of Brook Trout (Salvelinus fontinalis) in streams of the Shenandoah National Park.  These unproductive, small streams are lined with dense Rhododendron and trout cannot move to find more suitable habitats during most seasons.   Brook Trout have adapted to these southern highland streams.  Kelly's thesis project explored the relation between the energy available in drifting insect prey and growth and consumption of brook trout.  The field work required sampling every six hours, flushing out stomach contents with lavage, and quantifying the mass of all items in stomachs and in the drift.  The waterproof, Ryan J (chart recording) thermograph recorded water temperatures continuously in this pre-digital era. The field work was strenuous enough just to hike into the study areas. Once there, you realized just how mal-adapted bipedal hominids are for wading these streams.  Few investigators have attempted this type of work, especially over the 24-hour cycle.  Kelly was interested in the challenge and was attracted to studying native Brook Trout in their natural habitats.    While in the Peace Corps, stationed in Lesotho, in southern Africa, Kelly managed to apply his skill set to survey isolated populations of the critically endangered Maloti Minnow Pseudobarbus quathlambae.  This minnow is still struggling to persist today (see recent story).
A mountain stream of Virginia and home to the native Brook Trout.
Kelly's thesis findings are significant to the survival and persistence of Brook Trout.   The southern strain of Brook Trout are adapted to life in the small, infertile mountain streams but growth rates can be very slow and adult body size is modest.   In some streams, the amount of energy Brook Trout could assimilate was barely enough to meet their standard metabolic needs, much less to permit energy for activity or growth.  Very few mountain streams provide the right combination of habitats and food.
Differences between assimilated and maintenance energy for Brook Trout in four study streams in Shenandoah National Park (Meyer 1990).

Consequently, it is the rare Brook Trout that captures sufficient prey and meets energetic needs to live and swim and grow large enough to produce mature eggs and contribute to the next generation.   Brook Trout in these mountain streams continuously monitor the available drifting insects and dart out to capture the larger, more energetically valuable prey. The best streams have an abundant canopy to shade the stream and keep water cool enough for optimum Brook Trout feeding (12-17°C).   The optimal Brook Trout streams also produce an abundant and diverse fauna of invertebrates, including aquatic and terrestrial forms.   Kelly's hypothesis that growth and consumption of Brook Trout was influenced by abundance of larger prey in the drift was supported by his field studies (see below), especially within streams.   He also identified an energy minimizing strategy by the Brook Trout that enabled them to reduce activity costs when prey levels were low.  Years later, Railsback and Rose (1999) confirmed that  growth of Rainbow Trout was strongly influenced by factors controlling food consumption.  Their work and most other more recent field investigations relied on model-estimated food consumption rather than diel sampling.  
Percent of consumption captured by Brook Trout in relation to density of large drifting prey (Meyer 1990)
One of the surprises in the study was the regular appearance Gypsy Moth (Lymatria dispar)  larvae in the guts of the Brook Trout.   Gypsy Moths are a devastating forest pest that feed on foliage and were marching through the Appalachian mountains at that time.   The pest has been in North American for 100 years. A major concern is the potential loss of economically critical and ecologically dominant oak (Quercus spp.) trees.  Yet, the examination of the diet demonstrated that this terrestrial pest was subsiding the Brook Trout in these forest-covered mountain streams.

Realizing the practical difficulties for numerous intensive field investigations, Kelly Meyer also developed an energetics-based model to analyze dynamics of trout populations in Appalachian streams.  The model included mathematical formulations for temperature effects, size-dependent mortality, seasonal mortality to predict population changes and  average trout size.  The model was programmed in the language of the times (FORTRAN).   These calculations are essential components to define the thermal niche of the Brook Trout.  They may be used in future efforts to project the effects of climate change on suitability of streams for Brook Trout in the southern Appalachian mountains.  Many partners are involved via the Eastern Brook Trout Joint Venture, to protect, restore, and enhance remaining Brook Trout 

Most of Kelly's fisheries career was with the White Mountain Apache Tribe Game and Fish Department and  Arizona Department of Game and Fish.  When he was first hired, he was the only fisheries biologist with the White Mountain Apache Tribe; he would joke that he was Chief of Fisheries.  In this role, his expertise was critical in the management and recovery of the federally endangered Apache Trout (Oncorhynchus apache).  Many actions are required for the recovery of  Apache Trout and the success of recovery depends on special people, such as Kelly Meyer, who possess the patience and skills to work with the many cooperators to set appropriate fishing regulations, improve stream habitats, negotiate agreements, install and maintain barriers, and prevent movements of non-native competitors.  He was a field scientist for all seasons and for all peoples.  We need more people like Kelly Meyer in this world.   I am very saddened with news of his passing.

REST IN PEACE
Kelly J. Meyer
1961-2015

References
Meyer, K. J. 1990.  Effects of drifting prey abundance on food consumption and growth of brook trout in Shenandoah National Park.  Master's Thesis. Virginia Polytechnic Institute and State University, Blacksburg, Virginia.  111 pp.
Meyer, K.J., and D.J. Orth.  1990.  Development and application of an energetics-based model for trout populations in Appalachian streams.  Final Report, U.S.D.A. Forest Service, Southern Forest Experiment Station. 129 pp.
Railsback, S.F., and K.A. Rose. 1999.  Bioenergetic modeling of stream trout growth: temperature and food consumption effects.  Transactions of the American Fisheries Society  128:241-256.


Friday, April 26, 2013

Suckers Spawning on Virginia Tech Campus in Stormwater Inlet, by Don Orth



On Wednesday, April 24th, I hiked over to the VT Veterinary Medicine stormwater pond to check for spawning activity.   In April 2010 I got an email from Mike Rosenzweig, Director of Blacksburg Nature Center and Biology Instructor, who asked me about the identity of large fish in the pond inlet.    When I went to investigate I discovered these were white suckers and they were spawning in the inlet.    I have been watching the inlet since late March but have seen no evidence, presumably because of our cool spring this year.  Last Wednesday I observed at least 2 dozen large adult males congregating near the pond inlet.   Two had already swam up the bedrock shelf that separates the pond and the culvert under the walking path.   So sucker spawning season has begun and one can easily observe this phenomenon on campus.   
Male white sucker with breeding coloration pattern.  Photo by Ryan McManamay.



In 2010, Ryan McManamay, Tyler Young, and I took advantage of the opportunity to ask several questions:  Was this suboptimal spawning microhabitat or is it similar to habitats where white sucker normally spawn?  Did the spawning result in successful fertilization and development of embryos?   Are the reproductive needs of this population being met in small remnants of a natural channel in an otherwise human created system?     Over a two-week period we counted spawning suckers, collected and measured males and females, described spawning habitats, and collected drifting larval white suckers.  These observations are summarized in “Spawning of White Sucker (Catostomus commersoni) in a Stormwater Pond Inlet,” published in the American Midland Naturalist.  
  
We learned that the water source for this stormwater pond originates in a heavily modified subwatershed that is 41% impervious surfaces; the remainder is the VT baseball and softball fields, sports practice fields, track and football stadium, all of which are designed to rapidly shed rainwater.    The upper areas of the watershed include Stadium Woods and many grated inlets that intercept runoff and route the flow to a cluster of culverts that merge in to a concrete-lined tunnel feeding the inlet.  The day-lighted portion of the inlet is only 45 meters before entering the pond.   Stadium Woods, a controversial site for expansion of athletics practice fields, is a forest on the border of campus, and features 46 white oaks that are over 250 years old.   From a hydrological standpoint, this forest is the source of the cool, perennial flow that enters the pond inlet, yet the original spring and stream channel is buried, replaced by culverts.  All that remains of the natural channel is the 45 meters stretch.

Stormwater pond inlet stream used by spawning white suckers.  Photo by Ryan McManamay.


White suckers are known for their migratory runs in spring.  They spawn in swift flowing, shallow waters over gravel or cobbles, where they deposit adhesive eggs.   On a single day we estimated there were between 200 and 300 white suckers spawning in this small inlet.  We believe this to be the peak day of spawning as numbers dwindled appreciably thereafter.   These fish were demonstrating all the classic sucker spawning behaviors in the inlet stream as well as in the concrete tunnel, which has a thick deposit of fine gravel.    The stream temperature at this time (12.4 C) was 7.6 C cooler than the pond’s littoral zone.    Further, we documented fertilized eggs in the drift 8 days later and larval stages 12 days later.   Although I have unwittingly driven by this small pond inlet numerous times, I have never sampled it for fish.  But at least once per year it becomes an essential habitat for completing the life cycle.    It is shallower than other streams where white suckers spawn, but the velocities and bottom sediments were within the preferred range established by other investigators. 

Underwater photo of white suckers in inlet stream. Photo by Ryan McManamay.


The good news is that this highly modified watershed and pond system has a remnant 45-meter natural channel that sustains the reproductive needs of the pond population.  For local fish enthusiasts, now is the time to sit near the bank and observe the spawning behavior.   It will be over soon.     Observe and report.   I think you will agree that "Fish are awesome!"