SearcharxivSearch

arXiv · 2511.07575

The First Mathematical Model for Elk Wolf Interaction in Yellowstone National Park Using the E-SINDy Algorithm

Abstract

In this study, we investigate the prey predator dynamics of the elk wolf system in northern Yellowstone National Park, USA, using a data driven modeling approach. We used yearly population data for elk and wolves from 1995 to 2022 to construct a mathematical model using a sparse regression modeling framework. To the best of our knowledge, no previous work has applied this framework to capture elk wolf interactions over this time period. Our modeling pipeline integrates Gaussian process regression for data smoothing, sparse identification of nonlinear dynamics for model discovery, and model selection techniques to identify the most suitable mathematical representation. The resulting model is analyzed for its nonlinear dynamics with ecologically meaningful parameters. Stability and bifurcation analyzes are then performed to understand the systems qualitative behavior. A saddle node bifurcation identifies parameter ranges where both species can coexist, while regions outside this range may lead to the extinction of one or both populations. Hopf and saddle node bifurcations together delineate zones of stable co existence, periodic oscillations, and extinction scenarios. Furthermore, co dimension two bifurcations, including Bogdanov Takens and cusp bifurcations, are explored by varying two parameters simultaneously. Ecologically, these bifurcations reflect the complex interplay between wolf pressure and elk defence mechanisms, such as grouping or herd behavior. They suggested that small changes in ecological parameters can lead to sudden shifts in population outcomes ranging from stable co existence to extinction or oscillatory cycles.

Explore related subjects

Keep this discovery

BibTeXRIS

Anurag Singh, Nitu Kumari, Arun Kumar. 2025-11-10. The First Mathematical Model for Elk Wolf Interaction in Yellowstone National Park Using the E-SINDy Algorithm. https://arxiv.org/abs/2511.07575

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Admissible Fourier Lengths, KAM Reducibility, and Spectral Applications

We develop a perturbative KAM reducibility theory for one-frequency $\mathrm{SL}(2,\mathbb{R})$ cocycles based on an admissible Fourier length $\ell$. The regularity relevant to the iteration is measured by positive adapted Fourier width rather than ordinary smoothness in the Euclidean length $|n|$. The same length governs Fourier decay, truncation and resonance scales, and the arithmetic condition controlling the small divisors. This framework contains the classical analytic and Gevrey settings, while non-monotone choices of $\ell$ allow classical nowhere differentiable Weierstrass-type perturbations and continuous perturbations outside every positive H\"older class. As spectral applications, we obtain purely absolutely continuous spectrum for every phase and $1/2$-H\"older continuity of the integrated density of states for the associated quasiperiodic Schr\"odinger operators. The Aubry dual has pure point spectrum for Lebesgue almost every dual phase, with eigenfunctions exponentially localized in the metric induced by $\ell$. We also construct nowhere differentiable quasiperiodic potentials with purely absolutely continuous Cantor spectrum.

math.DS

Dynamics inside the attracting basins of some skew products

Polynomial skew products in $\mathbb{C}^2$ are maps of the form $F(z,w)=(P(z),Q(z,w))$, where $P$ and $Q$ are polynomials. Their local dynamics have been widely investigated. In this paper, we study the global dynamics inside Fatou components of some skew products. We consider all the inverse images in a Fatou component of a given point and use the Kobayashi metric to measure the distance between points. In the cases we consider, there are always arbitrarily large Kobayashi balls in the complement of these inverse sets.

math.DS

Ergodicity of dynamical systems without uniqueness of orbits

Recently, there has been considerable interest in the study of non-deterministic dynamical systems. To analyze the chaotic behavior of such systems from a measure-theoretic viewpoint, it is desirable to consider ergodicity. However, the classical definition of ergodicity involves invariant sets, whose definition is not unique for non-deterministic dynamical systems. Thus, we are led to the question of which invariance yields an interesting definition of ergodicity. Here, we propose a definition based on the strong backward invariance and show that analogs of classical results hold. We also consider implications of the Birkhoff ergodic theorem for systems without uniqueness of orbits.

math.DS