Dr. Robert Humston

It saddens me to report that the VMI Fish Ecology and Aquatic Research Unit is no longer in existence.

I have moved to a new position at Washington and Lee University.  I should have a website up and running there in the next few months.  In the meantime, you can contact me at humstonr@wlu.edu.

To all the friends, colleagues, and especially CADETS who made the FEAR Unit what it was: thanks for all your help.

See you on the water.

       The official lab acronym and logo:                                    Some photos from the F.E.A.R. Unit:

Research Interests:

►  Dispersal and spatial population ecology

►  Fish movement behavior and habitat associations

►  Management of fisheries, particularly sport / recreational fisheries

►  Ecological modeling for conservation and management planning

Current Projects:

Smallmouth Bass Dispersal and Otolith Chemistry:  My students and I are using trace element chemistry of smallmouth bass (Micropterus dolomieu) otoliths to study movement of juvenile and adult bass between the upper James River and its tributary Maury River.  The unique chemistry of each river - and even within distinct 'reaches' within these rivers - is recorded in the bass otoliths (ear stones) and preserved there as the fish grow.  We have successfully used otolith chemistry to distinguish natal origins of young-of-year fish, and recently applied these same spatial 'signatures' to estimate dispersal of recruits between rivers in their first year.  Our current focus is on determining if these chemical signatures change from year to year, or within-years, and if the growth of fish from larvae to juveniles affects the incorporation of elements into their otoliths.  This research is currently funded by a grant from the Jeffress Memorial Trust.

Basin-Scale Patterns of Recruitment Exchange and Population Genetics in River-Tributary Networks

The smallmouth bass otolith chemistry research is part of a larger effort to understand the spatial structure of fish populations in connected river systems.  Specifically, we're interested in looking at movement of juveniles and adults between connected rivers and how this contributes to (potential) metapopulation dynamics among the main stem of a river and its larger tributaries.  Our study system is the Upper James River and its larger tributaries.  This research is a collaborative effort with Eric Hallerman (Fisheries & Wildlife, VA Tech) and Simon Thorrold  (Woods Hole Oceanographic Institution).

Our plan is to use molecular (microsatellite) methods to assess genetic variation across the Upper James basin and among its major tributaries.  At the same time, we will employ otolith chemistry methods to track exchange of juveniles (recruits) between populations in the tributaries and main stem river.  Otolith methods will indicate how much exchange occurs between rivers, while the genetic analyses will determine if  this exchange contributes to reproduction and population growth in the James River or its tributaries.  Results from this research will be useful for managing fish populations in these systems.  If tributaries are important sources (or sinks) for recruitment in the James River population then land use, water quality, and fishery harvest regulations in these rivers will have important impacts on the James River fishery.

Fish Movement Behavior and Impacts on Population / Fishery Dynamics

As the tools available to study fish movement become increasingly sophisticated, we are learning more and more about the movement behavior of fish and the role such behavior can play in population / fishery dynamics.  The tools available to study fish movement today are amazing.  While the research described above is focused on large- or coarse-scale movements (dispersal and migration), these events are the result of small-scale movements and the constant interaction between individual fish and their surrounding environment.  In the near future I plan to couple tracking and mark-recapture experiments with those ongoing studies to attempt to understand how individual behavior leads to these population-level dynamics.  Currently, I am developing collaborations with scientists at the Virginia Institute of Marine Science and Universidade do Amazonas (Manaus, Brazil) to study movement behavior of other species using telemetry and otolith chemistry data.  I'll post more information about these projects as possible.