Anthony Ricciardi
@ecoinvasions.bsky.social
Ecologist (invasive species, freshwater biodiversity, bioinvasions, aquatic ecosystems) | Professor of Biology, McGill University | Director of the Bieler School of Environment | My lab account: @ricciardilab.bsky.social
Environmental science
69%
Geography
17%
Tensions mount over conflicting ballast water regulations on the Great Lakes
American shippers are at odds with the Canadian government over its regulations that require all Great Lakes vessels or “lakers” to install systems to treat their ballast water by 2030.
www.wpr.org
Both countries have harmonized regs for ships entering the seaway, mandating saltwater flushing of ballast tanks. Lakers (domestic ships) are exempt. But they move organisms between ports in the Great Lakes. Canada requires them to install systems to treat ballast water. www.wpr.org/news/conflic...
Biodiversity concerns set to be the next frontier after climate change
With the rise of natural capital initiatives such as the TNFD, systemic risk issues related to ecosystem collapse will soon receive the same amount of attention as climate change
www.iflr.com
In the 1960s NATO scientists treated biodiversity as a strategic asset. Inspired by Charles Elton, they viewed complex ecosystems as being less vulnerable to disruption by warfare: www.nytimes.com/2013/05/30/o.... Now economists are recognizing risks of biodiversity loss www.iflr.com/article/2a63...
2/2] The study supports the view (Ricciardi et al. 2011) that invasions should be managed as natural disasters, with similar investments in infrastructure & emergency response plans to protect against extreme events (like a major earthquake or wildfire) whose occurrence is unlikely but unacceptable.
Biological invasions are as costly as natural hazards
Natural hazards — such as storms, floods, and wildfires — can be disastrous phenomena and so can biological invasions, for which impacts are often irr…
www.sciencedirect.com
Another reminder: Biological invasions are at least as costly as earthquakes, floods & wildfires. Their prevention deserves similar precautionary investments as those applied to extreme natural hazards. #bioinvasions
www.sciencedirect.com/science/arti...
www.sciencedirect.com/science/arti...
Invasive species cost humans $423bn each year and threaten world’s diversity
At least 3,500 harmful invasive species recorded in every region on Earth spread by human activity, says UN report
www.theguardian.com
A reminder, from the 2023 IPBES assessment of invasive alien species. www.theguardian.com/environment/...
Exactly How Much Life Is on Earth? (Published 2023)
www.nytimes.com
Quote: "There are a more living cells on Earth — a million trillion trillion (or 10^30 in math notation, a 1 followed by 30 zeros) — than there are stars in the universe or grains of sand on our planet."
www.nytimes.com/2023/12/01/s...
www.nytimes.com/2023/12/01/s...
Controversial view: If one defines 'nonnative' in evolutionary terms (as I do), then humans are properly viewed as nonnative outside of Africa. If you define 'invasive' as being superabundant, spreading rapidly & causing ecological disruption, then the human species fits that definition too. 🧵 1/n
Agreed.
bsky.app/profile/ecoi...
bsky.app/profile/ecoi...
Reposted by Anthony Ricciardi
What can the emerald ash borer reveal about the long-ago loss of American chestnut? • New Hampshire Bulletin
For more than 70 years, the American chestnut tree has, mostly, been absent from the landscape. But historical accounts of its grandeur and the tons of nutritious seeds it produced every fall have mad...
newhampshirebulletin.com
Researchers in New Hampshire are studying how ash loss from #EmeraldAshBorer may mirror the disappearance of American chestnut, tracking impacts on forest biodiversity, soil and ecosystem health.
Read more: newhampshirebulletin.com/2025/10/13/w...
#InvasiveSpecies #Entomology 🧪🌍🍁
Read more: newhampshirebulletin.com/2025/10/13/w...
#InvasiveSpecies #Entomology 🧪🌍🍁
Two flawed rhetorical arguments are repeatedly used to downplay the risks of introduced non-native species.
One argument is:
“The vast majority of non-native species are not a threat to native biodiversity or ecosystems (so concern about them is overblown)”.
This overlooks a few crucial points...🧵
One argument is:
“The vast majority of non-native species are not a threat to native biodiversity or ecosystems (so concern about them is overblown)”.
This overlooks a few crucial points...🧵
Invasion impacts in terrestrial ecosystems: Global patterns and predictors
Biological invasions can alter ecosystems, yet their impacts vary across ecological contexts. Using a global meta-analysis of 775 studies (2223 effect sizes) in terrestrial systems, we show that the m...
www.science.org
Quote: "Invasive plants generally had negative effects on native plant diversity & greenhouse gas emissions. Native plant diversity was not a strong predictor of invasive plants’ effects. [Diversity decreased] the longer the invasive species was present" #bioinvasions www.science.org/doi/10.1126/...
1/🧵 Over the past decade, misinformation in the popular media & the opinion pages of some journals has promoted the claim that concern over species invasions is overblown, because "most invasions do not cause extinctions".
Here is a brief reminder of what scientific evidence shows...
#bioinvasions
Here is a brief reminder of what scientific evidence shows...
#bioinvasions
Quote: "75% of Kilimanjaro’s indigenous plants had been wiped out over the last century. The main cause: intensive land use by farmers & builders; the loss of the plants’ natural habitats; and increasing numbers of non-indigenous, partly invasive plants."
Reposted by Anthony Ricciardi
Reposted by Anthony Ricciardi, Stephen D. Murphy
Mythbusting de-extinction to sort fact from fiction
De-extinction hit the headlines recently with the ‘resurrection’ of the dire wolf and the push to bring back the moa. However, can scientists really bring back extinct animals? And more importantly, s...
www.sciencelearn.org.nz
The wonderful people at the NZ Science Learning Hub have turned my talk on MythBusting de-extinction to sort fact from fiction into a freely available educational resource. You can check it out here www.sciencelearn.org.nz/resources/my...
Safeguarding long-term research in ecology and evolution - Nature Ecology & Evolution
Long-term research projects are essential for predicting the ecological and evolutionary responses of species to global change, yet their continuity is often threatened by uncertainties over funding. ...
www.nature.com
Safeguarding long-term research in ecology and evolution www.nature.com/articles/s41...
Q&A with Stéphane Blanc, research director at CNRS, about the Long-term Studies in Ecology and Evolution programme and its priorities for supporting long-term monitoring and research
Free to read: rdcu.be/eQltU
Q&A with Stéphane Blanc, research director at CNRS, about the Long-term Studies in Ecology and Evolution programme and its priorities for supporting long-term monitoring and research
Free to read: rdcu.be/eQltU
3/3] Consensus on its non-native status would probably depend on the amount of divergence; but would we have the luxury of knowing this in advance?
I would argue that planetary protection protocols should treat *any* microbe being returned to Earth from space as potentially invasive or damaging.
I would argue that planetary protection protocols should treat *any* microbe being returned to Earth from space as potentially invasive or damaging.
Planetary Biosecurity: Applying Invasion Science to Prevent Biological Contamination from Space Travel
Abstract. As plans for space exploration and commercial use expand rapidly, biosecurity measures and risk assessments that inform them must adapt. Sophisti
academic.oup.com
2/n] This would constitute a case of 'back contamination' & fall in the domain of invasion risk assessment. The same applies to any organism that (say) mutated after being introduced to Mars by previous missions, if it contaminates samples that are returned to Earth.
academic.oup.com/bioscience/a...
academic.oup.com/bioscience/a...
Bacteria Found On The International Space Station Are Mutating To Become Functionally Distinct - Astrobiology
strains of the bacterial species Enterobacter bugandensis isolated from the International Space Station (ISS) were studied.
astrobiology.com
Lichen has survived 18 months attached to the outside of the Int'l Space Station.
If a microbe mutated while in space (as has happened already: astrobiology.com/2024/04/bact...) & was subsequently introduced back to Earth, should it be considered a non-native species?
My answer would be yes. [1/🧵]
If a microbe mutated while in space (as has happened already: astrobiology.com/2024/04/bact...) & was subsequently introduced back to Earth, should it be considered a non-native species?
My answer would be yes. [1/🧵]
Reposted by Patrick A. Jansen
Team of international experts call for urgent action against increasing threat from invasive species
While invasive alien species have long been recognized as a major threat to nature and people, urgent action now is needed to tackle this global issue. This is the critical evaluation by the 88 author...
phys.org
A warning by scientists.
Owing to interactions among drivers, and the increasing spread of new & well-established alien species, "simple extrapolations from the impacts of invasive alien species observed today are likely to underestimate the magnitude of future impacts."
phys.org/news/2024-06...
Owing to interactions among drivers, and the increasing spread of new & well-established alien species, "simple extrapolations from the impacts of invasive alien species observed today are likely to underestimate the magnitude of future impacts."
phys.org/news/2024-06...
Telecoupling and the spillover system: Causes and effects of zebra mussels in the Great Lakes
Examining the impacts of zebra mussels in the Great Lakes and beyond.
www.canr.msu.edu
A common claim is that zebra mussels "clean" lakes. They can certainly clear the water column but also create conditions that reduce oxygen & promote toxic algal blooms:
phys.org/news/2021-06...
www.canr.msu.edu/news/telecou...
cdnsciencepub.com/doi/10.1139/...
www.greatlakesnow.org/2021/07/rese...
phys.org/news/2021-06...
www.canr.msu.edu/news/telecou...
cdnsciencepub.com/doi/10.1139/...
www.greatlakesnow.org/2021/07/rese...
Reposted by Julie L. Lockwood
Businesses can’t build resilience without nature strategies
Businesses must develop nature strategies and implement them swiftly to mitigate risks and build resilience in a changing world.
www.eco-business.com
"When ecosystems fail, supply chains stall, costs spike, and financial stability is eroded.
The World Economic Forum ranks biodiversity loss and extreme weather among the decade’s top global risks.
Yet, most companies leave nature out of their strategic plans."
www.eco-business.com/opinion/busi...
The World Economic Forum ranks biodiversity loss and extreme weather among the decade’s top global risks.
Yet, most companies leave nature out of their strategic plans."
www.eco-business.com/opinion/busi...
Rob Colautti also wrote a thoughtful review in NeoBiota:
neobiota.pensoft.net/article/77920/
neobiota.pensoft.net/article/77920/
In the British Ecological Society magazine 'The Niche' (Winter 2020), Phil Hulme wrote a nice review of our new edition.
It has been 5 yrs since Dan Simberloff & I developed an annotated 2nd edition of Charles Elton's famous 1958 monograph "The Ecology of invasions by Animals and Plants". We added 9 new chapter forewords, an introduction & a conclusion - all of which aimed to place Elton's ideas into a modern context.
Reposted by Graeme S. Cumming, Julie L. Lockwood
There are no remote regions in a globalized world. The Antarctic region (ice-free peninsula, coastal waters, & surrounding islands) has been invaded by ~200 species of plants, animals, & microbes. Antarctica is connected to the world by global ship traffic. #bioinvasions
www.pnas.org/doi/full/10....
www.pnas.org/doi/full/10....