Melissa Merrick

I am a Wildlife Biologist for the Mt. Graham red squirrel monitoring program (since 2005) and a PhD student (since 2009) in 

Wildlife Conservation and Management, both under Dr. John Koprowski. 

 

Prior to finishing my Bachelor’s degree, I began conducting research at the Rocky Mountain Biological Laboratory in Colorado with Dr. Rosemary Smith. Here, we studied small mammal communities along elevational gradients in montane meadows.  Additionally, we examined the population dynamics of burying beetles (Nicrophorus spp.), which require small mammal carcasses for reproduction, in the same montane meadows. We found that year t+1 beetle populations tracked year t small mammal abundance (Smith and Merrick 2001). For my Master’s degree, I studied the thermal biology of burying beetles along elevation gradients in Colorado and Idaho. I determined that thermoregulatory ability differed among species and thermal tolerances and thermoregulatory abilities of different beetle species may contribute to niche segregation and the ability to coexist in sympatry (Merrick and Smith 2004).  Altered temperature regimes and thermal profiles may affect species assemblages and distributions of many organisms, from plants and insects to mammals – including humans.

 

While working for Dr. Koprowski’s red squirrel monitoring program and conservation research laboratory, I have become increasingly

interested in the ecology of sky island mammals, particularly as it relates to species diversity, endemism, and space use in the face of multiple disturbance events such as fire and invasive species, which may threaten species persistence. My dissertation research is focused on juvenile Mt. Graham red squirrel survival, space use, and natal dispersal. Through my dissertation research, I hope to understand many things including:

1) What is the survival rate for juvenile Mt. Graham red squirrels?

2) Is natal dispersal sex biased? Who stays & who goes? How far do they go? How do these data compare to other “mainland” red squirrel populations?

3) How does a forest mosaic, altered by tree death and fire, influence movement behavior and habitat use? Is moving through altered forest patches potentially more risky?

4) We know a lot about why young animals may leave the natal area, but less is known about what factors influence the duration and extent of transitory exploration and which trigger settlement. I am testing several ideas related to these phases of natal dispersal, including natal habitat preference induction, local density of conspecifics, body condition, food and microclimate availability, and forest structure characteristics.  

 

Climatic extremes and increased disturbance events currently observed in the sky islands of the desert southwest are likely exemplary

of changes to come in other forest ecosystems via altered climate regimes. Understanding how forest obligates respond to and navigate 

such rapidly changing landscapes will be important as these changes could affect settlement behavior and associated costs for animals 

inhabiting forest ecosystems worldwide.

 

 

 

Merrick, M. J., J. L. Koprowski, R. N. Gwinn, G. H. Palmer, and C. A. Zugmeyer. 2011. Surveys to determine the status of red squirrels in Guadalupe Mountains National Park, Texas. The Southwestern Naturalist 56: 24-28.

Jessen, Rosa R., M. J. Merrick, J. L. Koprowski, and O. Ramirez. 2010. Presence of Guayaquil squirrels on the central coast of Peru: an apparent introduction. Mammalia 74: 443-444.

Merrick, M. J., R. N. Gwinn, R. L. Minor, R. R. Jessen, T. G. Jessen, V. L. Greer, and J. L. Koprowski. 2009. Endangered Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis) uses nest following lightning strike. The Southwestern Naturalist 55: 125-126.

Merrick, M. J., S. R. Bertelsen, and J. L. Koprowski. 2007. Characteristics of Mount Graham red squirrel nest sites in a mixed conifer forest. Journal of Wildlife Management 71: 1958-1963.

 

Merrick, M. J., and R. J. Smith. 2004. Temperature regulation in burying beetles (Nicrophorus spp.: Coleoptera:Silphidae): effects of body size, morphology, and environmental temperature. Journal of Experimental Biology 207: 723-733

 

Smith, R. J., and M. J. Merrick. 2001. Resource availability and population dynamics of Nicrophorus investigator, an obligate carrion breeder. Ecological Entomology 26:173-180

 

Smith, R. J., A. Hines, S. Richmond, M. Merrick, A. Drew, and R. Fargo. 2000. Altitudinal variation in body size and population density of Nicrophorus investigator (Coleoptera: Silphidae). Environmental Entomology 29:290-298