#biologicalinvasions — Public Fediverse posts

A 2026 article from the New Zealand Journal of Ecology is getting useful traction in the NZ media this month. David Norton, Peter Bellingham, and Sarah Richardson review the state of deer numbers and their impacts in NZ forests. and show that things are getting worse quickly. Their title summarises it well: "Deer in the headlights: sleepwalking our way to a native forest catastrophe."

Many species of deer were introduced into NZ for hunting and remain a popular resource and sport. However, they eat of lot of native plants and recreational hunting has not been sufficient to keep deer numbers from rising. More resourcing from the government is needed, and soon.

https://www.rnz.co.nz/news/environment/1296127/nz-sleepwalking-into-catastrophe-as-feral-deer-crisis-spirals-out-of-control

https://doi.org/10.20417/nzjecol.50.3639

#biosecurity #biologicalInvasions #pests #deer #nz #conservation

@rnzbot_nz These Wairarapa plants are a big southwards jump in the pasture weed *Senecio madagascariensis*, previously known from the north of NZ. While it seems to be national news today, the plants were first confirmed in the Wairarapa on iNaturalistNZ by talented young NZ botanist Marley Ford in January, and there are seven observations of it so far here on iNat, including a re-identification by Marley of a plant photographed in 2020.

It’s a tricky one to spot as the species is only subtly different in form from the more widespread southern African gravel groundsel, *Senecio skirrhodon*, which is much less problematic for pastoral farmers. The key to telling the species apart is the shape of the bracts at the base of the flowers.

https://www.inaturalist.nz/observations?nelat=-41.032530047&nelng=175.888055296&swlat=-41.982755499&swlng=174.888299436&taxon_id=168820

#weed #BiologicalInvasions #NZ #Senecio #botany #iNaturalist #iNaturalistNZ

This week I found what I think is the first wild seedling of a tulip tree I've seen in NZ. It's the first record of a wild tulip tree from the greater Christchurch area, and one of few from NZ, on #iNaturalist.

Why does this matter? Because this is how most tree weeds start. Ingo Kowarik's classic 1995 study from Branderburg, Germany, showed that "on average, there was a time lag of 147 years between the introduction to Brandenburg and the initiation of invasion (170 years for trees, 131 for shrubs)" and that the most successful invaders were not neccesarily the earliest to go wild.

My tulip tree seedling is the first offspring of two tulip trees planted on Lincoln University's campus about 60 years ago. The species had been rarely planted in the city until recently. It was fashionable at the time the city was rebuilt after the earthquakes, so now we've got lots of them planted. We may see many more wild tulip tree seedlings in another half century.

Time will tell how well suited it is to NZ's environments.

https://www.inaturalist.nz/observations/365601855

https://www.researchgate.net/profile/Ingo-Kowarik/publication/230693763_Time_lags_in_biological_invasions_with_regard_to_the_success_and_failure_of_alien_species/links/0912f50dc8d572fd12000000/Time-lags-in-biological-invasions-with-regard-to-the-success-and-failure-of-alien-species.pdf

#botany #weeds #BiologicalInvasions #WoodyWeeds #nz #Liriodendron

#NewPaper out: Twenty-five years of Neobiota: building a community for invasion science in Europe and beyond by Ingo Kowarik and many great colleagues @TheresaHenke

#alienspecies #biologicalinvasions #neobiota

https://neobiota.pensoft.net/article/173229/

Finally. It's out doi.org/10.1093/bios... Quantifying the magnitude of biological invasions using total biomass @[email protected] #invasivespecies #biologicalinvasions

Quantifying the Magnitude of B...

Finally. It's out doi.org/10.1093/bios... Quantifying the magnitude of biological invasions using total biomass @[email protected] #invasivespecies #biologicalinvasions

Quantifying the Magnitude of B...

I was reminded this week that trout in New Zealand rivers are introduced predators and that this is not good for some native fish.

I was up in the mountains at Craigieburn Forest Park on Thursday (scoping out a new university ecology field trip). One of our team thought she saw a trout in Cave Stream, and I got a quick photo.

We were with retired forester Nick Ledgard, who spent much of his career working here. He had seen native galaxid fish in the stream before and thought it was trout free, since trout would have difficulty getting up past the cave system that Cave Stream is known for.

Looking at my photo later, I unfortunately confirmed that it was a brown trout.

NZers love trout and trout management is an important way to advocate for cleaner rivers. Still, it is also important for native fish conservation (especially non-migratory galaxid fish) that some stretches of our rivers remain trout free.

http://inaturalist.nz/observations/328459396

#fish #nz #BiologicalInvasions #trout

Travis Wetland is a large urban wetland nature reserve. That means it's surrounded by people and their gardens on all sides, so it gets a constant inflow of pests (and pet cats) and weeds.

While working at the wetland yesterday, we found (and pulled out) the first records from the wetland of evergreen buckthorn and raphiolepis. Both are emergent woody weeds that are shade tolerant and make bird dispersed fleshy fruits. They're both still planted in gardens.

If you live near some wild native habitat, keep an eye out for new exotic plants establishing.

https://inaturalist.nz/observations/328034270

https://inaturalist.nz/observations/328034276

#weeds #wetland #nz #Christchurch #BiologicalInvasions #iNaturalistNZ

Tonight our teenage daughter asked if we could rewatch the old Cane Toad documentary, An Unnatural History. We’d played it for her when she was much younger and it had stuck with her. It’s still a cracker documentary, in equal measures informative and alarming and hilarious. One of the best. Also, it ends with a theme song written and sung by Tim Finn of Split Enz and Crowded House fame.

Worth a watch if you’ve not seen it.

https://www.youtube.com/watch?v=aZgm9yiGzEE

#CaneToads #NatureDocumentary #Australia #BiologicalInvasions

Huifei Jin et al. test the separate and combined effects of nutrient levels and nematodes on performance of individual invasive plant species, as well as their competition with native plant communities.

#BiologicalInvasions | #Exotic_nativeCompetition | #GlobalChange | #Nematode_plantInteractions | #ResourceAllocation

https://doi.org/10.1093/jpe/rtaf060

The American ragwort aphid is now up in the Christchurch Port Hills where it's feeding on native senecio plants. 😔

The species arrived in the city in autumn of 2019 and has been spreading since then. I found it last week on the top of Sugarloaf, which is the first record of the species in the hills beyond the city.

Things are going to get complicated when the aphid arrives at NZ's at-risk populations of threatened endemic senecios.

https://inaturalist.nz/observations/322653324

#BiologicalInvasions #aphids #insects #nz #iNaturalistNZ

Sensible advice from Greater Wellington Council: don’t keep pests as pets.

https://www.rnz.co.nz/news/national/576465/greater-wellington-council-wants-people-to-stop-adopting-possums-as-pets

#nz #pests #pets #BiologicalInvasions

Watch out: the weather is warming and the American ragwort aphids are *multiplying*.

American ragwort aphids specialise on Senecio plants, of which NZ has many species, including some threatened endemic species.

The aphid arrived in NZ (somehow) in 2023, and has since got to work munching on our plants. The American aphids are also now being tended and protected by exotic Australian ants.

In the South Island these aphids are still restricted to Christchurch city (at least based on observations on #iNaturalist and #GBIF).

It would be great if you could keep a look out for them in other places. They're the only big black aphid in NZ (black bodies and legs).

Here are three of my observations of them from this month.

#aphids #PlantInsectInteractions #herbivory #BiologicalInvasions #NZ #Christchurch #iNaturalistNZ #insects #entomology

https://inaturalist.nz/taxa/453265-Aphis-lugentis

Zhikun Ren et al. predicted the current and future global #PotentialGeographicalDistribution of Bidens pilosa by integrating climatic, human-induced and biodiversity factors.

#BiologicalInvasions | #ClimateChange | #EnvironmentalFactors | #HabitatSuitability | #NicheOverlap

https://doi.org/10.1093/jpe/rtaf032

Les invasions biologiques marines by Goulletquer, Philippe, 2024

Biological invasions are one of the main causes of biodiversity decline worldwide.
Philippe Goulletquer reviews the latest advances in research into the detection, prevention, control and management of marine invasive species, in the light of the new regulations in effect.

#OpenAccess

https://directory.doabooks.org/handle/20.500.12854/153495

#books
#French
#BiologicalInvasions

❓Nutrient addition ➕ nematodes ➡️ competition between invasive and native plants

Results:
1️⃣ High-nutrient ➡️ invasions⬆️; local plants competition ➡️ invasions⬇️.
2️⃣ Low-nutrient ➕ nematodes ➡️ invasions⬆️; High-nutrient ➕ nematodes ➡️ invasions⬇️.

#BiologicalInvasions | #Exotic-nativeCompetition | #GlobalChange | #Nematode-plantInteractions | #ResourceAllocation

https://doi.org/10.1093/jpe/rtaf060

@dubh When it's done right, people can make a huge difference to NZ's environment by spotting emergent weeds as they're beginning to establish.

My favourite recent example is Dave Holland's discovery in 2020 of wild black swallow-wort on the edge of the Timaru Botanic Gardens. That was the first wild record of the species anywhere in NZ, and it's a wetland weed overseas. Timaru Council and Environment Canterbury staff stepped in with control, over several years, and now it's gone.

That's one environmental weed nipped in the bud before it could get started.

https://inaturalist.nz/observations/65849739

#weeds #BiologicalInvasions #InvasivePlants #eradication #ParticipatoryScience #WeedSurveillance

Ces #espècesexotiques qui étouffent la #biodiversité de #lareunion #lemonde #alieninvasivespecies #exoticspecies #biodiversity #biologicalinvasions
https://www.lemonde.fr/sciences/article/2025/05/12/ces-especes-exotiques-qui-etouffent-la-biodiversite-de-la-reunion_6605526_1650684.html

Harnessing traits to predict economic impacts from biological invasions www.sciencedirect.com/science/arti... #biologicalinvasions #invasivespecies

Harnessing traits to predict e...

Our new paper just out in @TrendsEcolEvo

Typology of the ecological impacts of biological invasions 🌏🧪

https://www.cell.com/trends/ecology-evolution/abstract/S0169-5347(25)00073-4

#invasivespecies #biologicalinvasions #ecologicalimpacts

Our new paper just out in @cp-trendsecolevo.bsky.social Typology of the ecological impacts of biological invasions 🌏🧪 www.cell.com/trends/ecolo... led by @laiscarneiro03.bsky.social @franckcourchamp.bsky.social #invasivespecies #biologicalinvasions #ecologicalimpacts

Typology of the ecological imp...

I'm at Lake Hāwea this week helping teach a field trip for our Masters level Conservation Biology course at #LincolnUniversityNZ. The surprise find so far has been the lizard team's discovery of redback spiders on the university's Mount Grand high country station.

These are Australian venomous spiders related to black widows and NZ's katipō. Redbacks have been established around Cromwell and Alexandra and are spreading.

https://inaturalist.nz/observations/269242334

#spiders #BiologicalInvasions #nz #iNaturalistNZ

#BiologicalInvasions expert Prof. Franz Essl from Austria gave a seminar today at #LincolnUniversityNZ. He showed a study of the global distribution of slugs and snails. Natives show distinct biogeographic regions. Australasian snails were different from African snails which were different from South American snails. Yet, naturalised snails (moved around the world by people) were just temperate and tropical. We are dramatically simplifying the natural world by moving species about. #molluscs

Yesterday I saw my 2nd "common" ectemnius, on a roadside near Lincoln, #NZ. This wasp is from Europe, Asia, & North America. It was first found in the southern hemisphere in Feb 2020 in Christchurch by Hannah Nolan, for her undergrad entomology collection at #LincolnUniversityNZ. It triggered a biosecurity response, and she passed the course.

There have now been 30 observations, all in and around Christchurch, as it slowly expands.

https://inaturalist.nz/observations/266870319

#insects #wasp #BiologicalInvasions

Little-humped spiders have reached Oxford! #iNaturalist user flamingtofunz posted a photo yesterday.

This Australian spider was found in NZ in 2016 in #Christchurch and has spread southeast (Little River by 2022), south (Leeston by 2024), north (Pegasus by 2024), and now northwest to Oxford.

It's a small, distinctive social spider. A few 100 spiders work together to build large messy webs that catch a lot of insects.

https://inaturalist.nz/observations/265494676

#iNaturalist #NZ #spiders #BiologicalInvasions

NeoBiota https://neobiota.pensoft.net/ the journal which I have the pleasure and honour of being chief editor for the past 14 years, increased its Scopus CiteScore for the third consecutive year to now 8.1 (the journal's all-time high). This means we are in Q1 of #AnimalScience and #Zoology; #InsectScience; #AquaticScience; Ecology, #Evolution, Behavior and #Systematics; #PlantScience; #Ecology; and #EcologicalModelling.

#AcademicChatter #AcademicPublishing #BiologicalInvasions #AlienSpecies

Here are 3 Australian critters I saw on my run yesterday in Ōtautahi-Christchurch, NZ. All are recent arrivals to the city and are spreading.

Little humped spiders showed up in 2014 and have since spread out to Pegasus, Leeston & Little River.

Passionvine hoppers showed up in Christchurch on iNaturalistNZ in 2016. They've exploded since & eat a wide range of plants.

Steelblue ladybirds first showed up in Christchurch in 2020.

#BiologicalInvasions #nature #EcologicalMonitoring #nz #WildCounts

🚨 New paper out! Here, we reveal the status of the invasion of Carpobrotus edulis in Uruguay (a species practically unreported in national herbariums) using data from #iNaturalits 🇺🇾 Spoiler alert: it's bad! https://doi.org/10.1007/s10530-023-03242-w #CitizenScience
#NaturalistaUY #BiologicalInvasions

A book chapter just published:

Joana Vicente et al. 2023. Modelling Invasion by Australian Acacia Species: Progress, Challenges and Opportunities. Wattles. CABI Books 496–513. https://doi.org/10.1079/9781800622197.0030

Please look at the full book "Wattles. Australian Acacia Species Around the World" by David M. Richardson, Johannes J. Le Roux, Elizabete Marchante:
https://doi.org/10.1079/9781800622197.0030

#ecology #biologicalInvasions #alienSpecies #newPublication
@alienspecies

Had a great time sharing some of my #PhD research at #ESA2023 last week!

#Ecology #Conservation #Research #InvasiveSpecies #BiologicalInvasions #PricklyPearProjectKenya

Our latest #InvaCost paper now out:

'Unveiling the hidden economic toll of biological invasions in the European Union'

https://enveurope.springeropen.com/articles/10.1186/s12302-023-00750-3

#invacost #invasivespecies #biologicalinvasions #EU #economics

“I don’t think we want to live in a global #suburbia. Why do you want to go to a place and see the same weeds you can see in your back garden?”

“We’ve introduced #ferals to the bottom of the world. They’re destroying it
Research published in Scientific Data this month suggests humans have introduced 1125 new species to the Southern Ocean islands, which surround #Antarctica, and 135 to the frozen continent itself. The list reads like an exotic menagerie: budgerigars, canaries, geese, terrapins, opossums, hedgehogs, pigs, reindeer, hamsters, foxes and even monkeys. These species have hunted local #seabirds and destroyed native plants. The problem is going to get worse. Australian explorers noted #dogs so feral they had basically become wolves.”

https://www.smh.com.au/national/we-ve-introduced-ferals-to-the-bottom-of-the-world-they-re-destroying-it-20230420-p5d1w1.html
#BiologicalInvasions #Cryosphere #AlienSpecies #Livestock #AntarcticTreaty #SettlerCulture

A new study (https://www.sciencedirect.com/science/article/pii/S2530064423000214) found that the global economic impact of biological invasions is equivalent in magnitude to that of natural disasters such as earthquakes, fires, floods and storms.

The costs of biological invasions have increased more rapidly than those of natural disasters over the past 4 decades.

Societies need to build a culture of safety & resilience against the threat of #BiologicalInvasions - just as we have done for natural hazards.
#InvasiveSpecies #AlienSpecies

#BOTD (March 29, 1900) Charles Elton: One of the most influential ecologists of the 20th century & the father of animal #ecology, who turned natural history into a science.

Elton founded the Journal of Animal Ecology, defined fundamental concepts and proposed hypotheses (niche, population cycles, diversity-stability, enemy release, etc) that continue to fuel research. Several decades ago, he recognized #BiologicalInvasions as a form of global change. And (like Hutchinson) he never had a PhD!

This weekend I found the first Harlequin ladybird we've ever seen at our house.

The species was first found in NZ in Auckland in April 2016, and #iNaturalist shows its rapid spread through the country. It first showed up in Ōtautahi-Christchurch city in April 2019.

It's much bigger than other ladybirds in NZ, and has a wide diet of smaller, soft-bodied insects like aphids, caterpillars, and ladybird larvae.

https://inaturalist.nz/observations/148714692

#insects #ladybird #Aotearoa #NZ #Biologicalinvasions

This is great willowherb, Epilobium hirsutum, an invasive wetland weed that arrived in NZ in 2018. I found this plant on Monday on the Worcester bridge in the centre of Ōtautahi-Christchurch. It likely spread from a fenced off empty section right next to Cathedral Square, that's filled with great willowherb in seed.

While we focus on making NZ "predator-free", our country is filling up with weeds.

https://inaturalist.nz/observations/148286207

https://www.mpi.govt.nz/news/media-releases/mpi-confirms-discovery-of-invasive-weed-great-willowherb-in-canterbury/

#BiologicalInvasions #weeds #Aotearoa #NZ

Here's something to look out for in NZ. Today Mike Bowie uploaded photos of a colony of red gum lerp psyllids that he found feeding on a eucalyptus tree in North Canterbury. It's the first time Mike had seen this species.

It's an Australian species that was first seen in New Zealand in 2017 and this is the first NZ observation on #iNaturalist.

The white circular juvenile "lerps" are distinctive.

https://inaturalist.nz/observations/148215074

#psyllid #Aotearoa #NZ #BiologicalInvasions #insects

@NessaUndreza Agave americana is well naturalised in New Zealand too. Here's a wild one in my neighbourhood that I photographed this weekend.
They also show up in NZ dunes, growing vegetatively out from runners.
https://inaturalist.nz/observations/147182735
#botany #weed #BiologicalInvasions #Aotearoa #NZ

@pogomcl Nice! The last time I saw a small tortoiseshell butterfly, it flew into my office window in Lincoln, New Zealand, in the middle of the 2019 winter.

Yes, the Southern Hemisphere is an exceptionally odd place to see a small tortoiseshell.

To my knowledge, it's still the first Australasian record of the species. It's now on a pin in the Lincoln University Entomology Museum.

https://inaturalist.nz/observations/30721349
#butterflies #Lepidoptera #insect #BiologicalInvasions #iNaturalistNZ #iNaturalist

#JobOffer Looking for a #PhD?! Want to play with drones and use satellite remote sensing to support catchment scale monitoring of #biocontrol of invasive plant species?! Apply now! @jobsecoevo #Job #phd #ecology #BiologicalInvasions #modelling #UK #EcoEvo
https://iapetus2.ac.uk/studentships/drone-and-satellite-remote-sensing-to-support-catchment-scale-monitoring-of-biocontrol-of-invasive-plant-species/

"I have saved until last the most terrifying story of all: the story of the fungus, Batrachochytrium dendrobatidis, ...Bd, that is not just killing individual frogs but wiping out so many kinds of frogs around the world. Almost all scientists working on Bd argue that the epidemic of disease has spread through global industrial shipping, particularly of commercial frog species that carry the fungus but do not die from it." #invasivespecies #biologicalinvasions
https://www.littletoller.co.uk/the-clearing/the-new-wild-by-anna-tsing/

I spent part of today showing Environment Canterbury staff the only known spot in the South Island with long-flowered Veldt grass, Ehrharta longiflora. It's a potential new weed, and it's so far only known from one location in Ōtautahi-Christchurch (at the base of Hackthorne Road). Please keep an eye out for it, and upload a photo to #iNaturalist if you think you've found it.
https://inaturalist.nz/observations/139094019
#weed #InvasiveWeed #BiologicalInvasions