Research

Integrative Ecology Across Scales

My research program investigates the physiological mechanisms that determine how organisms respond to environmental change. I work at the intersection of cellular biology, organismal physiology, and ecological dynamics, asking one major question -

How environmental stressors shape animal performance, and what determines species resilience?

By integrating measurements of energy metabolism, mitochondrial function, and whole-organism performance, I link ecological outcomes, like survival, distribution, and invasion success, with their underlying mechanistic processes at the cellular level.

Research Themes

1. Climate Variability and Overwintering Physiology

Model System: Mountain pine beetle (Dendroctonus ponderosae), Emerald ash borer (Agrilus planipennis)

Location: Carleton University, ON, Canada (2022-2025)

Climate change is altering winter patterns across Canada, with consequences for insect populations, forest health, and ecosystem dynamics. My postdoctoral research investigated how winter timing influences energy balance in bark beetles—major forest pests expanding their range northward.

Key Questions:

How does winter onset timing affect energy accumulation in overwintering insects?
Can bark beetles resume feeding during warm winter periods?
What metabolic adaptations enable survival during prolonged cold exposure?

Key Findings:

Early, severe winters constrain energy accumulation, reducing survival and outbreak potential
Prolonged warm autumns enhance energy reserves and spring survival
Bark beetles can opportunistically feed during mid-winter warm periods

Impact: This work provides mechanistic insights for predicting pest population dynamics under climate change, directly informing forest management strategies.

Selected Publication:

Haider, F., Roe, A.D., Andersen, M.K., Liu, Y., Musso, A.E., Fudlosid, S., Evenden, M.L., MacMillan, H.A. (2025). Winter intensity shapes overwintering energy gain and use in bark beetles under range expansion. Journal of Experimental Biology, 229: jeb251414.

2. Multiple Stressor Effects in Coastal Ecosystems

Model System: Soft-shell clams (Mya arenaria), Blue mussels (Mytilus edulis)
Location: University of Rostock, Germany (2016-2019)
Coastal ecosystems face multiple simultaneous stressors—salinity fluctuations, mechanical disturbance, pollution, and climate change. How do organisms cope when physiological demands exceed cellular capacity?

Key Questions:

How do multiple stressors interact to affect organismal performance?
What role does mitochondrial function play in limiting behavioral responses?
Can we predict tipping points where organisms can no longer maintain homeostasis?
Key Findings:
Bivalves prioritize energetically costly escape behaviors over osmoregulatory stability under combined stress
Mitochondrial aerobic capacity limits burrowing performance in estuarine environments
Energy allocation trade-offs determine ecological success under multiple stressors

Impact: This work provides mechanistic insights for how environmetal stressors such as salinity fluctuation, mechanical disturbances, pollutants, food limitation, afftect the ecological services provided by molluscs, like clams and mussels.

Selected Publication:

Haider, F., Sokolov, E. P., Timm, S., Hagemann, M., Rayon, E. B., Marigomez, I., Izagirre, U., and Sokolova, I. M. (2019). Interactive effects of osmotic stress and burrowing activity on protein metabolism and muscle capacity in the softshell clam, Mya arenaria. Comparative Biochemistry and Physiology, Part A, 228:81-93.

Noor, M.N., Wu, F., Sokolov, E.P., Falfushynska, H., Timm, S., Haider, F., Sokolova, I.M. (2021). Salinity-dependent effects of ZnO nanoparticles on bioenergetics and intermediate metabolite homeostasis in a euryhaline marine bivalve, Mytilus edulis. Science of the Total Environment, 774.

Haider, F., Timm, S., Bruhns, T., Noor, M.M., Sokolova, I.M. (2020). Effects of prolonged food limitation on energy metabolism and burrowing activity of an infaunal marine bivalve, Mya arenaria. Comparative Biochemistry and Physiology, Part A, 250.

Haider, F., Sokolov, E. P., Timm, S., Hagemann, M., Rayon, E. B., Marigomez, I., Izagirre, U., and Sokolova, I. M. (2019). Interactive effects of osmotic stress and burrowing activity on protein metabolism and muscle capacity in the softshell clam Mya arenaria. Comparative Biochemistry and Physiology, Part A, 228:81-93.

Haider, F., Sokolov, E. P., and Sokolova, I. M. (2018). Effects of mechanical disturbance and salinity stress on bioenergetics and burrowing behavior of the soft-shell calm, Mya arenaria. Journal of Experimental Biology, 221(4): jeb172643.

3. Mitochondrial Mechanisms of Stress Tolerance

Model Systems: Ocean quahog (Arctica islandica), Marine bivalves

Location: University of Rostock, Germany (2019-2020); UNC Charlotte, USA (2014-2015)

Mitochondria are the powerhouses of cells, but they're also sensitive sensors of environmental stress. Understanding mitochondrial responses to fluctuating oxygen, temperature, and pH reveals fundamental mechanisms of physiological tolerance.

Key Findings:

Hypoxia-tolerant species modulate electron transport system capacity to prevent oxidative damage
Mitochondrial membrane potential regulation is critical during oxygen fluctuations
Ocean quahogs maintain mitochondrial quality control during hypoxia-reoxygenation cycles

Selected Publication:

Sokolova, I. M,. Sokolov, E. P., Haider, F., (2019). Mitochondrial mechanisms underlying tolerance to fluctuating oxygen conditions: lesson from hypoxia-tolerant organisms. Integrative and Comparative Biology, 59(4):938-952.
Haider, F., Falfushynska, H., Ivanina, A. V., and Sokolova, I. M. (2016). Effect of pH and bicarbonate on mitochondrial functions of marine bivalves. Comparative Biolchemistry and Physiology, Part A., 198:41-50.

Future Research Directions

Physiological Tolerance and Invasion Success

Building on my expertise in stress physiology and bioenergetics, I want to explore what are the markers that differentitate the native and invasive species.

Why do some species thrive under environmental extremes while others decline?

My goal is to compare physiological tolerance between native and invasive invertebrate species in terrestrial and freshwater systems. I want to focus my studies on examining bioenergetics and mitochondrial physiology of my model organisms, identify markers to specific environmental stressors. This will help me to collaborate with researchers to develop predictive models and build resilience map under changing climate.