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Course:CONS200/2025WT2/The Role of Megafauna in Ecosystem Health and Stability: History and Case Studies in British Columbia, Canada

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Introduction

Megafauna live across the world in varying ecosystems and environments, providing the planet with an array of diversity. Although they are known for their large size, megafauna are not always appreciated for their role in ecosystem health and stability across the world. The history of megafauna plays a significant role in the abundance of plant and animal species today and emphasizes the critical environmental benefits large wildlife provides. Megafauna have been declining since the late Pleistocene, and consequently, there have been detrimental ecosystem effects.[1] Subsequently, habitats and species dynamics look different today than they did during these historical time periods. Scientists now recognize that the loss of megafauna has the potential to cause trophic cascades and consequently impact habitat and species dynamics and behaviour, biogeochemical cycling and invasive species control. [2][3][4]Therefore, understanding the complex dynamics of megafauna and the ecosystem services they provide is critical in the ways conservationists and scientists manage species going forward. Ultimately, conservation efforts to conserve and protect megafauna in their natural habitats are imperative for the future of ecosystems globally.

Background

Definitions

A giraffe (Giraffa camelopardalis, left) and a black rhinoceros (Diceros bicornis, right), two extant examples of savanna megafauna

Megafauna (literally ‘large animals’), is a term widely used in ecology referring to the largest animals within a given ecosystem.[5] Such animals often have a variety of effects on the dynamics of ecosystems.[1][6] Megafauna are typically defined by a mass- or length-based threshold dependant on the scale of an ecosystem, for instance, soil megafauna comprise organisms such as earthworms, while savanna megafauna encompass rhinos, elephants and other such animals.[5]

Biogeochemical cycles are chains of chemical reactions on a planetary scale that drive the movement of various chemicals, including major components of biological nutrients such as carbon and nitrogen [7] These arise from tectonic and atmospheric interactions, enabling chemical bonds to form and break between important elements, and are further facilitated by microbes to form molecules used in biological processes such as nitrate and ammonia [7].

Nutrient cycling is the movement of nutrients in biogeochemical cycles between their consumers and the environment, and it includes the movement of nutrients within soil, plants and soil organisms [8]

[9]. Molecules from global biogeochemical cycles are often involved in nutrient cycling[10]. Various ecosystem functions, such as water purification, are tied to the efficacy of nutrient cycling [8]. Animals, including megafauna, can influence nutrient cycling through herbivory, seed dispersal and other behaviors that can alter the movement of nutrients.[11]

History

Large mammal populations over time in different landmasses, before (green) and after (yellow) arrival of humans

Megafauna have been present on Earth since 567 million years ago[3], excluding a period following the Cretacecous mass extinction.[2] However, a notable decrease has been observed in terrestrial megafauna populations and diversity within the past 50,000 years, which has been attributed to impacts from human activity.[3] This trend was first observed in the Early Pleistocene in Africa, coinciding with the hominid Homo erectus developing fire usage and larger brains, taking on predatory roles in the region.[2] Since then, this trend expanded to encompass other regions globally, coinciding with the arrival of humans and human ancestors.[2]

Several factors are thought to be responsible for this change. Early humans were thought to have been effective predators in their time, which can be attributed to two advantages they had over other large carnivores. Firstly, early humans were omnivorous and could maintain pressure on animal populations even if prey wasn’t abundant.[2] Another advantage early humans possessed was the ability to use projectiles and kill prey at a safe distance [link]. Alongside direct predation by humans, other secondary effects may have also contributed to megafauna decline. Domesticated dogs may have competed with native carnivores over resources, placing additional pressure on them.[2] The loss of herbivores may have also created cascading effects across ecosystems as a result of changes in vegetation, disturbance regimes and prey availability, leading to further extinctions.[2] It should be noted, however, that much of these impacts primarily affected terrestrial megafauna prior to recorded history, and that anthropogenic effects on marine megafauna are more recent.[2] In modern times, both terrestrial and marine megafauna face decline from various anthropogenic effects, intentional and unintentional [link, link]. The primary factor driving megafauna extinction is harvesting, most commonly for consumption purposes but also for other reasons such as the usage of body parts for trophies or medicine [link]. Other factors exist, such as from pollution and development driving habitat degradation as well as climate change [link, [7]].

Ecosystem Functions of Megafauna

Megafauna have numerous significant ecosystem functions, such as nutrient storage, transport and cycling along with the consequences should they be lost.[1][6] These processes impact ecosystem dynamics and health, and contribute to the sustainability of major earth systems.

Nutrient Cycling

Brown bears (Ursus arctos) eating and disposing of salmon carcasses in riparian zones

Megafauna have significant roles in nutrient cycling and the biogeochemical cycle due to their assistance in nutrient transport. An example of megafauna assisted nutrient cycling is the relationship between bears and salmon in riparian zones. For brown bears (Ursus arctos), a common megafauna found in North America, salmon is an important component in their diet, however, this not only sustains these creatures but contributes greatly to nitrogen cycling in riparian zones.[12] Being the main source of plant-available (inorganic) nitrogen, but low in abundance, ammonium (NH4+) and nitrate (NO3-) have significant impacts on soil and plant health.[12] By excreting and discarding salmon carcasses, bears were found to increase these inorganic nitrogen pools by three times.[12] In fact, it was found that when salmon carcasses are placed directly on soil, they increase sediment nitrification, making nutrients available to plants by 25-fold.[13] Ultimately, the deposition of salmon-derived nutrients via bears has favourable impacts on nitrogen mineralization and nitrification in riparian zones.[12] The nitrogen availability brown bears provide can increase plant productivity, microbial activity and ultimately biodiversity which is sustained through the abundance of plant species. These significant impacts of megafauna indicate the key roles they play in the biogeochemical cycle.

Habitat Dynamics and Ecosystem Function

Grazing megafauna in tallgrass prairie ecosystem

While megafauna are known primarily for their great size, they contribute significantly to the maintenance of ecosystems, particularly that of plant diversity. In locations with substantial plant productivity, the presence of large herbivores acted as an asset in increasing plant diversity, but had the opposite effect in areas with low plant productivity.[14] The correlation between large herbivores and plant diversity in areas of high productivity indicates that in the right environment, megafauna play a significant role in species abundance and diversity in ecosystems. In particular, grasslands with high productivity rely greatly on large grazers to maintain their diversity and without the ecosystem services megafauna provide, the future of these sparse grasslands could be at risk.[14] In fact, in a tallgrass prairie, increased bison space use was found to be positively correlated with species diversity, causing a greater presence of forbs.[15] This beneficial relationship is apparent in the environmental alterations which contribute to balancing such ecosystems and therefore increase biodiversity.

African savanna elephant (Loxodonta africana) herbivory

Furthermore, elephants, including the African savanna elephant (Loxodonta africana) and the Asian elephant (Elephas maximus), provide numerous ecosystem services across their natural ranges. In many parts of the world, elephants are keystone species, meaning that they have critical impacts on a multitude of other species and ecosystem cycles and dynamics.[16] Elephants play a crucial role in habitat structure, as well as species abundance and diversity.[16] Studies find that elephants expand carbon stored aboveground by 7% as a result of stand thinning, which ultimately increases the size of trees and increases carbon sequestration.[16] Additionally, elephants contribute to drought survival for numerous species through their ability to dig water holes.[16] Carbon storage and water abundance during drought are critical issues, especially in hot and dry locations across Africa where the African savanna elephant resides. The alterations of habitats result in the growth of healthy ecosystems which promote the abundance of species and species diversity.

Marine Ecosystems and Megafauna

Process of biological pump and whale pump in marine ecosystem

Not only do megafauna have significant environmental benefits in terrestrial ecosystems, but they play a crucial role in the function of marine habitats. Baleen whales (Mysticeti) and sperm whales (Physeter macrocephalus) are part of the great whale group, and are known for their colossal size.[17] Great whales exhibit numerous marine ecosystem functions through predation, whale pumps and whale falls.[17] Whales directly and indirectly affect marine ecosystems through food-webs and predation, and are thought to contribute to the cycling of carbon and other nutrients vertically and horizontally in the ocean.[17] Whale pump is the process by which whales mix and transport nutrients through varying layers of the ocean, resulting in greater ecosystem productivity.[17] Not only does whale pump contribute to the mixing of stratified ocean layers, but the presence of fecal plumes near the surface, a result of their feeding locations, spreads nutrients throughout the ocean.[17] Phytoplankton thrive on the deposition of whale feces and thus transport nutrients to the deep sea.[17] Furthermore, whale falls is a term used to describe whales sinking to the seabed once deceased.[18] The decaying carcasses provide a feast of nutrients for ocean floor species, including chemosynthetic communities which are defined by their use of chemicals as a source of energy.[18] However, not all whale carcasses sink, in fact, due to the presence of gas as they decompose, 10% of dead whales alternatively float.[18] This creates a plentiful food source for a number of species, including orcas and sharks, as well as coastal scavengers once the carcass washes to shore.[18] Ultimately, while alive and dead, whales are beneficial in nutrient supply and cycling, as well as the balance of species throughout the ocean. Marine megafauna provides multiple ecosystem services to sustain a top-down change of species.

Case Studies in British Columbia, Canada

Broad ecological concepts like nutrient cycling, and food web dynamics, describe the functions of megafauna in ecosystems [2][5]. However, specific case studies exemplify these processes in action. In British Columbia, the relationship between megafauna and their environments reveal how ecosystems respond to both natural and human behaviors.[19] The following examples examine how whales, and other deep-sea megafauna influence – and are influenced by – their habitats, including the coasts, and ocean.

Deep-sea Megafauna and Bottom Trawling off the Coast of British Columbia

Off the coast of Vancouver Island, deep-sea megafauna such as sea cucumbers, brittle stars, rockfish, and thorny head fishes, play an important role in maintaining ocean floor ecosystems. These species are vital to the deep-water communities which support ecosystem services like nutrient cycling, carbon storage, and sediment mixing. [6][19] However, human activity, in particular, bottom trawling, has disrupted these ecological processes significantly.

Bottom trawling, a fishing method that drags heavy nets along the seafloor, has been widely used in British Columbia since the 1990s.[19] The thornyhead (Sebastolobus ssp.) fishery in particular targets areas between 500 and 1100 meters deep, overlapping with zones where these megafaunas are most active.[19] This practice leaves deep grooves in the sediment and disturbs habitats supporting these slow-growing megafauna species.

One study using over 50 kilometers of remotely operated vehicle (ROV) footage found that trawled areas had lower species diversity and fewer animals overall.[19] These areas also coincide with zones of low oxygen levels, making recovery even more difficult. Only a few hypoxia-tolerant species, such as thornyheads, remain prevalent where fishing pressure is highest.[19]

This case study highlights the sensitive nature of deep-sea ecosystems to human exploitation and shows how megafauna support seafloor productivity and stability within British Columbia. When these species are disrupted or removed, the ecosystems they anchor tend to lose biodiversity and resilience, two key indicators of ecosystem health.

Underwater view of humpback whale rear trailed by fishing line
Humpback Whale (Megaptera novaeangliae) entangled by fishing line

Humpback Whales and Coastal Aquaculture

Baleen whales, including humpback whales (Megaptera novaeangliae), are vital to ocean ecosystems [6]. As filter feeders, they consume vast amounts of krill and small fish, then rise to release nutrient-rich waste at the surface. This process, sometimes called the “whale pump,” fertilizes phytoplankton, and in turn supports primary producers and food web stability [20]. These microscopic plants form the base of marine food webs and help absorb carbon, making whale activity essential to both biodiversity and climate regulation [6].

In British Columbia, humpback populations have been steadily recovering from a history of commercial whaling. However, growing human activity along the coast, such as shipping, tourism, and aquaculture has introduced new risks. One significant source of concern is the rise of open-net pen salmon farms, enclosures placed in ocean waters to raise fish. These facilities bring heavy vessel traffic, noise pollution, and infrastructure into the same water channels used by humpbacks for feeding and migration [20].

A 2024 study documented eight cases of humpbacks becoming entangled in aquaculture equipment from 2008 to 2021, including three deaths. Most incidents involved young whales and occurred in nets or as a result of anchor lines used by the farms [20]. These events represent a fraction of all entanglements in the region but demonstrate how commercial infrastructure poses real risks to recovering whale populations.

Given their ecological role in ocean productivity, any reduction in humpback numbers could degrade the ecosystem services they support. Even without major population loss, disruptions to whale behavior and habitat risks reducing the stability and health of BC’s marine ecosystems [6] [20].

The Future of Megafauna

Importance in Maintaining Ecosystems

Megafauna loss is associated with various major and detrimental effects to ecosystem functioning. The extirpation of megafauna from an ecosystem can lead to further loss of any organisms dependent on them, including parasites, predators and mutualistic partners.[3] This loss can also result in a decrease in the movement capacity of organisms between ecosystems, such as through the dispersal of plant seeds via said megafauna.[4] As a result of these effects, other secondary impacts can subsequently occur. Megafauna loss can trigger trophic cascades that alter the flow of energy between organisms, and therefore the abundance of affected organisms in ecosystems.[2] Remaining organisms, including ones dependent on megafauna, may exhibit morphological and behavioural shifts, including anachronisms, adaptations that are no longer advantageous and reflect past ecological interactions.[3] The extinction of megafauna also leads to a loss of redundancy among niches, especially amongst species of different sizes dependent on the same resources[21] .

Alongside such effects, there are also detrimental results from the loss of megafauna specific to the role they play in an ecosystem. The loss of herbivores leads to an overall decrease in vegetation consumption, which in turn, can lead to negative secondary effects [22]. For instance, such extirpation can lead to a loss of nutrient cycling maintenance within the local environment.[2] It can also lead to a decrease in herbivory regulating populations of certain plants, loss of seed dispersal vectors and shifts in disturbance regimes to favour fire, ultimately resulting in altered plant composition within a given habitat.[2] [7]On the contrary, carnivore losses lead to uncontrolled herbivore population growth, leading to simplified ecosystems with less resilience and redundancy.[2] In addition, the loss of large carnivores removes a potential control for invasive animals, both herbivorous and carnivorous.[2]

Future Projections

Megafauna are decreasing in numbers with many species going extinct [23]. Decreasing megafauna can cause changes in species abundance and composition, ultimately altering whole ecosystems [24]. The loss of megafauna can also affect seed dispersal due to the plants reliance on megafauna for moving its seeds to new locations.[4] Without megafauna, biodiversity will decrease because megafauna movement connects ecosystems, and without connectivity between ecosystems, the diversity of species cannot be maintained.[4] Additionally, the extinction of megafauna also decreases biodiversity as a number of the species that co-evolved with the megafuana become extinct.[3] The species that co-evolved with them will become extinct because they are specifically adapted to the interaction with megafauna and without the megafauna, the adaptation will be useless and the species cannot survive.[3] Some species that co-evolved with megafauna will experience phenotypic and/or behavioural changes because the traits and/or behaviours were adapted alongside the megafauna and without the megafauna there is no need for those traits [3], or species will have anachronisms, which are traits that are not advantageous because the traits were adapted for extinct megafauna.[3]

Solutions and Conservation Efforts

Wolves being reintroduced at Yellowstone National Park, USA

There are many strategies to help megafauna from protected areas to reintroduction [23]. Reintroduction has been done successfully several times. An example of this is the reintroduction of wolves in Yellowstone National Park [23]. To help megafauna survive there needs to be effort from all levels of government such as international agreements or local policies protecting megafauna [23]. One conservation effort is to raise the public's awareness about the importance of megafauna and why the reintroduction of megafauna is needed [25]. Another approach is ex-situ conservation for endangered species that live in unstable political situations to protect them [26].

Conclusion

Megafauna play a crucial role in the maintenance and preservation of nutrient cycling, ecosystem functions, as well as, species diversity and abundance. As a result of the incremental spread of human populations and human activity across the globe, the abundance of megafauna has drastically decreased.[3] The steep decline in megafauna has led to detrimental ecosystem effects, including habitat alterations and loss of biodiversity.[16] Megafauna, such as bears and whales, can facilitate nutrient cycling through the movement of nutrients throughout ecosystems.[12][17] Without the maintenance services that megafauna provide, forest and grassland systems experience uncontrolled growth which has the potential to decrease carbon storage in trees, limit diversity and increase competition.[14][16] Moreover, without the careful consideration of the role that megafauna play in ecosystems, there is a possibility of extinction in co-existing species.[3] Therefore, the protection of such species is crucial for not only biodiversity, but to create and sustain healthy ecosystems.

References

  1. ↑ 1.0 1.1 1.2 Termes, L.; Keddie, G.; Hebda, R.; Trask, P.; Arbour, V.; Speller, C.; Paskulin, L.; Ramsey, C.; Richards, M. P. (2024). "Survival of mammoths (Mammuthus sp.) into the Late Pleistocene in Southwestern British Columbia (Vancouver Island), Canada". Canadian Journal of Earth Sciences. 61 (8): 843–854.
  2. ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 Malhi, Y.; Doughty, C. E.; Galetti, M.; Smith, F. A.; Svenning, J. C.; Terborgh, J. W. (2016). "Megafauna and ecosystem function from the pleistocene to the anthropocene". Proceedings of the National Academy of Sciences. 113 (4): 838–846.
  3. ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 Galetti, M.; Moleón, M.; Jordano, P.; Pires, M. M.; Guimarães, P. R.; Pape, T.; Nichols, E.; Hansen, D.; Olesen, J. M.; Munk, M.; de Mattos, J. S.; Schweiger, A. H.; Owen‐Smith, N.; Johnson, C. N.; Marquis, R. J.; Svenning, J. (2017). "Ecological and evolutionary legacy of megafauna extinctions". Biological Reviews. 93 (2): 845–862.CS1 maint: multiple names: authors list (link)
  4. ↑ 4.0 4.1 4.2 4.3 Berti, E.; Svenning, J. (2020). "Megafauna extinctions have reduced biotic connectivity worldwide". Global Ecology and Biogeography. 29 (12): 2131–2142.
  5. ↑ 5.0 5.1 5.2 Moleón, M.; Sánchez-Zapata, J. A.; Donázar, J. A.; Revilla, E.; Martín-López, B.; Gutiérrez-Cánovas, C.; Getz, W. M.; Morales-Reyes, Z.; Campos-Arceiz, A.; Crowder, L. B.; Galetti, M.; González-Suárez, M.; He, F.; Jordano, P.; Lewison, R.; Naidoo, R.; Owen-Smith, N.; Selva, N.; Svenning, J. C.; Tella, J. L.; Zarfl, C.; Jahnig, S. C.; Hayward, M. W.; Faurby, S.; Garcia, N.; Barnosky, A. D.; Tockner, K. (2020). "Rethinking megafauna". Proceedings of the Royal Society B: Biological Sciences. 287 (1922): 2019–2643.CS1 maint: multiple names: authors list (link)
  6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 Tavares, D. C.; Moura, J. F.; Acevedo-Trejos, E.; Merico, A. (2019). "raits Shared by Marine Megafauna and Their Relationships With Ecosystem Functions and Services". Frontiers in Marine Science. 6.
  7. ↑ 7.0 7.1 7.2 7.3 Falkowski, Paul; Fenchel, Tom; Delong, Edward (May 23, 2008). ""The Microbial Engines That Drive Earth's Biogeochemical Cycles"". JSTOR. Cite error: Invalid <ref> tag; name ":13" defined multiple times with different content
  8. ↑ Fontaine, Sébastien; Abbadie, Luc; Aubert, Michaël; Alvarez, Gaël. ""Plant–soil synchrony in nutrient cycles: Learning from ecosystems to design sustainable agrosystems"". Wiley.
  9. ↑ McCary, Matthew; Schmitz, Oswald (30 March 2021). ""Invertebrate functional traits and terrestrial nutrient cycling: Insights from a global meta-analysis"". British Ecological Society.
  10. ↑ Schröder, J; Schulte, R; Creamer, E; Delgado, A; Leeuwen, T; Rutgers, M; Spiegel, H; Staes, J; Wall, D (16 September 2016). ""The elusive role of soil quality in nutrient cycling: a review"". British Society of Soil Science.
  11. ↑ Berzaghi, F.; Verbeeck, H; Nielsen, M. R.; Doughty, C. E.; Bretagnolle, F.; Marchetti, M.; Scarascia-Mugnozza, G. (2018). "Assessing the role of megafauna in tropical forest ecosystems and niogeochemical cycles - the potential of vegetation models". Ecography. 41: 1934–1954.
  12. ↑ 12.0 12.1 12.2 12.3 12.4 Holtgrieve, G. W.; Schindler, D. E.; Jewett, P. K. (2009). "Large predators and biogeochemical hotspots: Brown bear (ursus arctos) predation on salmon alters nitrogen cycling in riparian soils". Ecological Research. 24 (5): 1125–1135.
  13. ↑ Levi, P. S.; Tank, J. L.; Tiegs, S. D.; Chaloner, D. T.; Lamberti, G. A. (2012). "Biogeochemical transformation of a nutrient subsidy: Salmon, streams, and nitrification". Biogeochemistry. 113 (1–3): 643–655.
  14. ↑ 14.0 14.1 14.2 Bakker, E. S.; Ritchie, M. E.; Olff, H.; Milchunas, D. G.; Knops, J. M. (2006). "Herbivore impact on grassland plant diversity depends on habitat productivity and herbivore size". Ecology Letters. 9 (7): 780–788.
  15. ↑ Ling, B.; Raynor, E. J.; Joern, A.; Goodin, D. G. (2023). "Dynamic plant–herbivore interactions between bison space use and vegetation heterogeneity in a tallgrass prairie". Remote Sensing. 15 (22): 52–69.
  16. ↑ 16.0 16.1 16.2 16.3 16.4 16.5 Van de Water, A.; Henley, M.; Bates, L.; Slotow, R. (2022). "The value of elephants: A pluralist approach". Ecosystem Services. 58 (101488).
  17. ↑ 17.0 17.1 17.2 17.3 17.4 17.5 17.6 Roman, J.; Estes, J. A.; Morissette, L.; Smith, C.; Costa, D.; McCarthy, J.; Nation, J.; Nicol, S., Pershing, A.; Smetacek, V. (2014). "Whales as marine ecosystem engineers". Frontiers in Ecology and the Environment. 12 (7): 377–385.CS1 maint: multiple names: authors list (link)
  18. ↑ 18.0 18.1 18.2 18.3 Quaggiotto, M.; Sánchez-Zapata, J. A.; Bailey, D. M.; Payo-Payo, A.; Navarro, J.; Brownlow, A.; Deaville, R;, Lambertucci, S. A.; Selva, N.; Cortés-Avizanda, A.; Hiraldo, F.; Donázar, J. A.; Moleón, M. (2022). "Past, present and future of the ecosystem services provided by cetacean carcasses". Ecosystem Services. 54 (101406).CS1 maint: multiple names: authors list (link)
  19. ↑ 19.0 19.1 19.2 19.3 19.4 19.5 De Leo, F. C.; Gauthier, M.; Nephin, J.; Mihály, S.; Juniper, S. K. (2017). "Bottom trawling and oxygen minimum zone influences on continental slope benthic community structure off Vancouver Island (NE Pacific)". Deep Sea Research Pat II: Topical Studies in Oceanograpy. 137: 404–419.
  20. ↑ 20.0 20.1 20.2 20.3 Cottrell, B.; Roth, M.; Lehnhart, T.; Snyman, H.; Trites, A. W.; Raverty, S. A.; Storlund, R. L.; Cottrell, P. E. (March 20 2024). "Aquaculture related humpback whale entanglements in coastal waters of British Columbia from 2008–2021". PLoS One – via National Institute of Health. Check date values in: |date= (help)
  21. ↑ Lyons, S. K.; Elliot Smith, E. A.; Smith, F. A. (Sep 19 2022). "Late Pleistocene megafauna extinction leads to missing pieces of ecological space in a North American mammal community". Proceedings of the National Academy of Sciences of the United States of America. 119: 39 – via Pubmed Central. Check date values in: |date= (help)
  22. ↑ Pederson, Rasmus; Faurby, Søren (Oct 17 2022). "Late-Quaternary megafauna extinctions have strongly reduced mammalian vegetation consumption". Global Ecology and Biogeography – via Wiley. line feed character in |title= at position 60 (help); Check date values in: |date= (help)
  23. ↑ 23.0 23.1 23.2 23.3 Ripple, William J.; Guillame, Chapron (2016). "Saving the World's Terrestrial Megafauna". Bioscience – via JSTOR.
  24. ↑ Berti, E. (Summer 2020). "Megafauna extinctions have reduced biotic connectivity worldwide". Global Geography and Biogeography – via Wiley Online Library.
  25. ↑ Ahkshik, A. (Spring 2022). "Equifinal paths to megafauna conservation through memorable wildlife tourism experiences: evidence from the restitution of the European bison (Bison bonasus) in Poland". Current Issues in tourism. – via taylor and francis.
  26. ↑ Farhadinia, M. (2020). "Ex situ management as insurance against extinction of mammalian megafauna in an uncertain world". Society for Conservation Biology – via Society for Conservation Biology.
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