Journal of Threatened
Taxa | www.threatenedtaxa.org | 26 November 2023 | 15(11): 24266–24276
ISSN 0974-7907
(Online) | ISSN 0974-7893 (Print)
https://doi.org/10.11609/jott.8576.15.11.24266-24276
#8576 | Received 07 June 2023 | Final received 12 August 2023 | Finally
accepted 16 October 2023
Mapping invasive alien plants
through citizen science: shortlisting species of concern for the Nilgiris
Shiny Mariam Rehel
1, R.S. Reshnu Raj 2, Samuel Thomas
3, Milind Bunyan 4, Anita Varghese 5
& Ankila J. Hiremath
6
1,5 Keystone Foundation, Groves hill
road, Kotagiri, The Nilgiris,
Tamil Nadu 643217, India.
2,4,6 Ashoka
Trust for Research in Ecology and the Environment (ATREE), Royal Enclave, Sriramapura, Jakkur PO,
Bengaluru, Karnataka 560064, India.
3
International Centre for Integrated Mountain Development, GPO Box 3226,
Kathmandu, Nepal.
1 shiny@keystone-foundation.org
(corresponding author), 2 reshnu.raj@atree.org, 3
samuel.thomas@icimod.org,
4 milind.bunyan@atree.org, 5 anita@keystone-foundation.org,
6 hiremath@atree.org
Editor: Aparna Watve,
Biome Conservation Foundation, Pune, India. Date of publication: 26 November
2023 (online & print)
Citation: Rehel, S.M., R.S.R. Raj, S. Thomas, M. Bunyan, A.
Varghese & A.J. Hiremath (2023). Mapping
invasive alien plants through citizen science: shortlisting species of concern
for the Nilgiris. Journal of Threatened Taxa 15(11): 24266–24276. https://doi.org/10.11609/jott.8576.15.11.24266-24276
Copyright: © Rehel et al. 2023. Creative Commons Attribution 4.0
International License. JoTT allows unrestricted use, reproduction, and
distribution of this article in any medium by providing adequate credit to the
author(s) and the source of publication.
Funding: Royal Norwegian Embassy,International Development Research Centre - IDRC, Department for International Development-DFID, Collaborative Adaptation Research Initiative in Africa and Asia- Adaption at Scale in Semi Arid Regions- CARIAA_ASSAR, National Geographic Societ.
Competing interests: The authors declare no competing interests.
Author details: See end of this article.
Author contributions: SMR carried out the compilation of the database of invasive plants for the Nilgiris, prepared the poster on common invasive plants and participated in fieldwork. RR carried out the data analysis and participated in fieldwork. ST participated in
fieldwork, was involved in shorlisting and finalization of the invasive plant list, and contributed to poster preparation. MB designed the study, and participated in fieldwork. AV designed and planned the study and participated in fieldwork. AH conceptualized and designed the study and participated in field work. All authors were involved in drafting and revising the manuscript.
Acknowledgements: Support for this work came from a
Royal Norwegian Embassy grant to ATREE; a grant from IDRC and DFID, through the
CARIAA-ASSAR project; and a National Geographic Society grant to AJH. We thank
the Tamil Nadu Forest Department for taking us to their experimental plots in Hasanur; WWF-India for use of the Thengumarahada
Field Station, and Shiva Subramaniam of ATREE for developing the smart-phone
interface (on Google’s Open Data Kit) for citizen scientists to use in mapping
invasive species.
Abstract: Species introduced from elsewhere
are known as alien species. They may be introduced as crop plants or ornamental
plants, or for timber. A small proportion of introduced species can
become invasive thereby spreading at the cost of native species and habitats,
negatively affecting biodiversity, food security, and human wellbeing. Despite
the growing recognition of the threat of invasive alien species, we still lack
information about the distribution and abundance of species widely accepted to
be invasive. To address this information gap regarding invasive alien species
distributions, we initiated a pilot citizen science effort to create an atlas
of invasive plants in the Moyar-Bhavani landscape of
the Nilgiri District. We aimed, through this pilot
effort, to develop and test user-friendly mapping protocols and develop an
interface for citizen scientists to use. Ultimately, we hope to create a model
that can be scaled up to large conservation landscapes, such as the Western
Ghats, the Central Indian Highlands, and the Himalaya.
Keywords: Biodiversity, conservation,
introduced species, India, invasive species database, Moyar-Bhavani
watershed, non-native plants, protocol, stakeholder workshop, threat,
user-friendly, Western Ghats.
INTRODUCTION
People have
moved species around the globe since time immemorial for food, fibre, fuel, sport, and aesthetic reasons. Such species,
which have been introduced outside their natural range of distribution, are
referred to as ‘alien species’ (or introduced or exotic species). Most alien
species arrive in new environments intentionally, though some can arrive
inadvertently as contaminants on known introductions or simply as stowaways.
Examples of species introduced intentionally include plants and animals
introduced for food (e.g., the African Catfish Clarias
gariepinus), for timber and fuelwood (e.g., the
Black Wattle Acacia mearnsii), or those
introduced as ornamental plants (e.g., Lantana camara),
and for the aquarium and pet trade (e.g., the Goldfish Carassius
auratus and the Red-eared Slider Trachemys
scripta elegans). An
example of an inadvertent or accidental introduction is Parthenium hysterophorus, whose seeds are thought to have arrived
in India as a seed contaminant of wheat imported from the Americas.
Although
the vast majority of introduced species are of great value, a small proportion
of these can become invasive. This refers to their becoming widespread and
having negative impacts on biodiversity, ecosystem services, food security, or
human health and wellbeing. The Intergovernmental Science-Policy Platform on
Biodiversity and Ecosystem Services (IPBES) identifies invasive alien species
as amongst the greatest threats to biodiversity and ecosystem services
globally, comparable with climate change, change in land (and sea) use, species
overexploitation, and pollution (IPBES 2019).
In India
too, we now recognise the threat of invasive alien
species. One of India’s National Biodiversity Targets (NBT4) focuses on
preventing new invasive species introductions and controlling existing invasive
species (MoEFCC 2014). Some states have gone further
by formulating policy on invasive species management, Tamil Nadu being the
first (TN-PIPER 2022).
Despite
this growing recognition of the threat of invasive alien species, we still lack
information about the distribution and abundance of species widely accepted to
be invasive. Such information is vital to prioritise
species and habitats for management interventions and provides a baseline
against which to assess future invasive species spread.
To address
this information gap regarding invasive alien species distributions, we initiated
a pilot citizen science effort to create an atlas of invasive plants in the Moyar-Bhavani landscape of the Nilgiri
District. Citizen science, which refers to a partnership between scientists and
members of the public, is a growing field both in India and globally. Over the
last decade the ubiquitousness of smartphones, plus
access to the internet, has made it easier for people to record and share
observations, leading to a growing number of such researcher-citizen scientist
collaborations (see for example, https://citsci-india.org/projects/). In our
specific case, scientists working in partnership with naturalists, students,
community members, and forest managers could achieve the task of mapping
invasive species at a scale, and within a timeframe, that would be meaningful
for both researchers and managers—something that scientists on their own could
not do. We aimed, through this pilot effort, to develop and test user-friendly
mapping protocols and develop an interface for citizen scientists to use. Ultimately,
we hoped to create a model that could be scaled up to large conservation
landscapes, such as the Western Ghats, the Central Indian Highlands, and the
Himalaya.
MATERIALS
AND METHODS
Description
of the study area
The Nilgiris District has a long history of plant
introductions. The cool, temperate upper elevations of the Nilgiris
attracted European settlers during the colonial period. They introduced many
alien species as garden ornamentals (e.g., Cestrum aurantiacum,
Asclepias curassavica,
and Cytisus scoparius)
and for fuelwood (e.g., Acacia mearnsii and Eucalyptus
spp.). Many of these species have since become invasive, suppressing native
species and altering habitats. The introduction of species to the Nilgiris continues to date, as the area is still of great
horticultural importance and remains a source of exotic fruits, vegetables, and
ornamental plants for the rest of southern India.
Our study
area, the Moyar-Bhavani watershed of the Nilgiris, straddles two terrestrial ecoregions—southern
Western Ghats moist deciduous forests and the southern Western Ghats montane
rainforests. We used the ecoregion information included in the Indian Alien
Flora Information database (v1.0 available at
https://ilora2020.wixsite.com/ilora2020/data) and identified 378 plant species
that have been introduced to these two terrestrial ecoregions (Pant et al.
2021). Of these, about 81 can be considered invasive alien species today, based
on expert opinion. However, we felt that mapping the distribution and abundance
of these many invasive species was an unreasonable ask of citizen scientists
(i.e., volunteers, students, and forest department field staff). We therefore prioritised amongst these 81 species to arrive at a more
manageable shortlist of widespread and highly invasive species for citizen
scientists to record. Here, we describe the process followed to create that
priority list of invasive species as a precursor to creating a pilot citizen
science atlas of invasive species.
Compiling,
selecting, and shortlisting of invasive species
As a first
step, in September 2017, we compiled a database of the 81 invasive plants for
the Nilgiris using various sources such as Zarri et al. (2004), Keystone Foundation (2008, 2016),
Narasimhan (2009), Khuroo et al. (2012), Hiremath & Sundaram (2013), and from personal
observations. For each species, we included additional information on its
origin, the range of elevations within which it is found, and its presence (or
absence) in various habitats. We created a matrix to indicate species presence
in these different habitats, i.e., dry and wet forest, grasslands, plantations,
wetlands (marshes, peat bogs), and freshwater habitats (ponds, lakes, rivers,
reservoirs) (Annexure 1).
The next
step was to select a preliminary short-list of invasive species from amongst
this list of 81 species. Our selection was informed by existing definitions of
invasive species. The IPBES defines an invasive alien species based on its
ecological and socio-economic impacts (IPBES 2019). An alternative definition
is proposed by Colautti & MacIsaac
(2004), who suggest that an invasive species is one that is both locally
abundant, and widespread, distinguishing it from other introduced species. We
combined these considerations into the following three criteria:
Species
that were well known in the landscapes (a measure of the species’ impacts and
abundance)
Species
that have spread into multiple habitats (a measure of the species’ local
abundance).
Species
that occur over more than one altitudinal zone (a measure of the species’
spread).
We
shortlisted 34 species that met these three criteria (Annexure 2) and convened
a stakeholder workshop later that same month to assess the appropriateness of
the shortlist for the Nilgiris landscape. A scoring
was done to reflect the presence of the species in different habitats, with ‘1’
denoting a species’ presence in only one habitat, ‘2’ denoting its presence in
two habitats, and so on.
The
stakeholder workshop included participants from local conservation organisations, community-based organisations,
academic institutions, and restoration practitioners. We added Pennisetum clandestinum
and Polygonum polystachyum to the final
shortlist during the workshop as these species were known to be spreading in
the Nilgiris. On the other hand, Acanthospermum
hispidum, Argemone
mexicana, Kalanchoe delagoensis,
Opuntia stricta, Synedrella
nodiflora, and Tithonia
diversifolia were excluded from the list because,
despite being invasive, these were not considered widespread by the stakeholders.
Later, we replaced Senna alata with Senna spectabilis after observing the rapid spread of Senna
spectabilis during a field visit to Sathyamangalam Tiger Reserve, and
based on expert opinion that S. spectabilis is
of greater conservation concern.
Based on
the workshop discussions, we selected 26 of the 34 shortlisted species for
mapping invasive alien species in the Nilgiris
(Annexure 3). We then prepared a field identification key with images of the
plant parts (habit, twigs, leaves, flower, fruit, seeds) to help individuals
identify species while mapping invasive species in the field. A hard copy of
the field identification key was printed for reference. The naming of the
species has followed the International Plant Name Index (IPNI).
RESULTS AND
DISCUSSIONS
Over 70% of
the species that we prioritised for the Nilgiris were categorised as
‘invasive’ in existing databases of invasive alien plants in India, namely the
‘Khuroo list’ (Khuroo et
al. 2012) and the ILORA database (Pant et al. 2021) (Table 1). When comparing
our list of 26 invasive alien species with Khuroo’s,
we found 19 species were assigned the status ‘invasive’, Passiflora
mollissima was assigned the status ‘naturalised/invasive’, while Senna spectabilis
and Pennisetum clandestinum,
are considered to be ‘cultivated’ and ‘naturalized’, respectively. None of the
remaining four species—Cestrum aurantiacum, Gamochaeta purpurea,
Polygonum polystachyum, and Solanum mauritianum on our list appears on the Khuroo list, though several of their congeners do.
Meanwhile,
the ILORA database has additions to the list of alien species that were absent
in the Khuroo list. These include C. aurantiacum and S. mauritianum,
which are assigned the status ‘invasive’ and ‘naturalised
alien,’ respectively. Both species are on our priority list of 26 species.
Apart from this, the invasion status of some species from the Khuroo list has been revised in the ILORA database. For
example, Phragmites australis and Pistia stratiotes (again, both on our
priority list of 26 species), considered invasive in the Khuroo
list, are now listed as native in the ILORA database (ver. 1) and unlisted
altogether in an updated version (1.1); this may be due to their cryptogenic
origins. Overall, 24 out of the 26 invasive species shortlisted by us can be
found in the ILORA database, with the exception of P. polystachyum
and G. purpurea.
The
comparison of our list of priority invasive species for the Nilgiris
with the Khuroo list and the ILORA database offers
interesting insights. One is that invasion is a dynamic process, and a species’
invasion status could change over time. For example, the Khuroo
list (published in 2012) considered Senna spectabilis
to be ‘cultivated’, but in the short time since, Senna spectabilis
has become widespread and abundant in several parts of the Western Ghats,
including the Nilgiris. Recent work by Anoop et al.
(2021) suggests that elephants are aiding in its widespread and rapid
dispersal. This change in the species’ status is reflected in the ILORA database
(see Table 1), which was compiled a decade after the Khuroo
list.
Another
interesting insight is that a species’ ‘alien’ status is determined by
biogeographic boundaries, not by geopolitical ones. In this case, Polygonum polystachyum (Himalayan Knotweed), which is native to
the Indian Himalaya, does not appear on either the Khuroo
list or the ILORA database. However, stakeholders in the upper elevations of
the Nilgiris, a region that is biogeographically
distinct from the Himalaya, consider the species to be invasive.
Overall,
our results highlight the value of the ILORA databases as a starting point for
any effort to compile a locally relevant list of invasive species. The ILORA
database builds on the earlier Khuroo list, and also
incorporates information from other existing databases (see Pant et al. 2021),
making it the most comprehensive listing of invasive alien plants for India
today. However, this also makes the database unwieldy in smaller regions. For
instance, the ILORA database lists a staggering 120 invasive alien species for
the Moyar-Bhavani watershed, which barely extends
over 4,100 km2. This might be because the watershed straddles two
terrestrial ecoregions (i.e., the southern Western Ghats moist deciduous
forests and the southern Western Ghats montane rainforests). Nevertheless,
mapping the distribution and abundance of these many species is a daunting
task, even when energised by citizen-scientists.
Here, our priority list of 26 invasive alien species for the Nilgiris underscores the value of local expert opinion in
shortlisting species that are locally relevant. The ILORA database may still be
useful when developing lists for large landscapes or states, but local
expertise is invaluable in developing lists for smaller landscapes.
Local
expertise is also vital for identifying emerging threats. One illustration of
this is the expert inclusion of Cestrum aurantiacum
and Solanum mauritianum, neither of which
appears on the Khuroo list. Both species are
relatively recent additions to the database on alien species in India (even
though they are listed as invasive alien species in global databases such as
CABI and GISD). Another is the expert inclusion of Senna spectabilis,
which was earlier listed as cultivated (in 2012) and has now been listed as
invasive (in 2021). Given that published information about invasive species in
India is still incipient, and that a large proportion of this information is
dominated by a few species (Hiremath & Sundaram
2013), comprehensive databases like ILORA are constrained by the information
that they can build on. In such a situation, expert opinion of local community
members, forest managers and botanists must continue to inform the listing and prioritising of invasive alien species, in conjunction with
existing databases.
Conclusion
There are
an estimated 220–225 invasive alien plants in India (Khuroo
et al. 2012; Pant et al. 2021). A few, such as Lantana camara
and Prosopis juliflora are very widespread
(Hiremath & Sundaram 2013). Others are
more regional in their distribution, though locally abundant and widespread,
e.g., Acacia mearnsii in the upper elevation
regions of the Western Ghats (Nayak et al. 2023), or Anthemis
cotula in the Kashmir Himalaya (Reshi et al. 2012). Yet the distribution and abundance of
each invasive alien species, and even the number of invasive alien species, is
expected to change in time. A citizen-science approach is best placed to track
these changes and build an atlas of invasive alien plants for India.
To enable
citizen scientists to contribute easily and continuously to such an atlas, it
is important that they are not overwhelmed by the large number of invasive
alien plants across India. Instead, they need to work with a shorter list of
species that is relevant to the area they live in. The process that we have
followed for prioritising invasive plants for the Nilgiris could provide a replicable model for other regions
as well.
Table 1. A comparison of the
short-list of 26 priority invasive alien plants of the Nilgiris
with existing national invasive species lists (ILORA version 1 and version
1.1).
|
Accepted scientific name of
species |
Family |
Native region |
Invasion status (Khuroo list) |
Invasion status (ILORA) |
|
Acacia mearnsii
De Wild. |
Mimosaceae |
Australia |
In |
In |
|
Ageratina adenophora (Spreng.) R.M.King & H.Rob. |
Asteraceae |
Central America |
In |
In |
|
Ageratum conyzoides L. |
Asteraceae |
South America |
In |
In |
|
Ageratum houstonianum
Mill. |
Asteraceae |
Mexico |
In |
In |
|
Alternanthera philoxeroides (Mart.) Griseb. |
Amaranthaceae |
South America |
In |
In |
|
Asclepias curassavica R.Br. ex. DC. |
Asclepiadaceae |
Tropical America |
In |
In |
|
Bidens pilosa L. |
Asteraceae |
South America |
In |
In |
|
Cestrum aurantiacum
Lindl. |
Solanaceae |
Central America |
- |
In |
|
Chromolaena odorata (L.) King & Robin. |
Asteraceae |
Central America |
In |
In |
|
Cytisus scoparius (L.) Link |
Papilionaceae |
Europe |
In |
In |
|
Datura innoxia
Mill. |
Solanaceae |
South America |
In |
In |
|
Pontederia crassipes (Mart.) Solms. |
Pontederiaceae |
Brazil |
In |
In |
|
Gamochaeta purpurea (L.) Cabrera |
Asteraceae |
South America |
- |
- |
|
Lantana camara
L. |
Verbenaceae |
Tropical America |
In |
In |
|
Mikania micrantha
Kunth |
Asteraceae |
Tropical America |
In |
In |
|
Opuntia tuna (L.) Mill. |
Cactaceae |
Mexico |
In |
In |
|
Parthenium hysterophorus L. |
Asteraceae |
Central America |
In |
In |
|
Passiflora mollissima L.H.Bailey |
Passifloraceae |
Tropical South America |
N/I |
Nt |
|
Pennisetum clandestinum Hochst. ex Chiov. |
Poaceae |
Tropical Africa |
Nt |
Nt |
|
Phragmites australis
(Cav.) Trin. ex Steud. |
Poaceae |
Temperate Eurasia |
In |
Native (ver.1); absent in ver.1.1 |
|
Pistia stratiotes L. |
Araceae |
North America |
In |
Native (ver.1); absent in ver.1.1 |
|
Polygonum polystachyum Wall. ex Meisn. |
Polygonaceae |
Himalaya |
- |
- |
|
Prosopis juliflora
(Sw.) DC. |
Mimosaceae |
Mexico & Central America |
In |
In |
|
Senna spectabilis (DC.) H.S.Irwin & Barneby |
Caesalpiniaceae |
Tropical America |
Cl |
In |
|
Solanum mauritianum
Scop. |
Solanaceae |
South America |
- |
Nt |
|
Ulex europaeus L. |
Papilionaceae |
Europe |
In |
In (ver.1); absent in ver.1.1 |
Cl—Cultivated | Cs—Casual | C/N—
Casual/Naturalised | Nt—Naturalised alien | N/I—Naturalised/Invasive
| In—Invasive.
For
image - - click here for full PDF
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Annexure 1. Presence of invasive species in
different habitats.
|
|
Name of the species |
Family |
Common name |
Native |
Elevation |
Dry forests |
Wet forests |
Grasslands |
Plantations |
Wetlands/Marshes/ Peat bogs |
Freshwater
(Ponds/Rivers/Lakes/Reservoirs) |
Scoring |
Ref |
|
1 |
Alternanthera ficoidea (L.) P.Beauv. |
Amaranthaceae |
Red threads, Joseph’s coat |
Brazil |
100– 800 m |
|
|
|
|
₊ |
|
1 |
1,2 |
|
2 |
Alternanthera paronychioides A.St.-Hil. |
Amaranthaceae |
Smooth joy weed flower |
South America & West Indies |
Up to 800 m |
|
|
|
|
₊ |
|
1 |
1,3 |
|
4 |
Alternanthera philoxeroides (Mart.) Griseb. |
Amaranthaceae |
Alligator weed |
South America |
Up to 1,000 m |
|
|
|
|
₊ |
₊ |
2 |
1 |
|
5 |
Alternanthera sessilis (L.) DC. |
Amaranthaceae |
Sessile Joy weed |
Tropical America |
200–1,500 m |
₊ |
|
|
|
₊ |
₊ |
3 |
1 |
|
6 |
Amaranthus spinosus
L. |
Amaranthaceae |
Spiny Amaranthus |
America |
Up to 1,500 m |
₊ |
|
|
|
|
|
1 |
1 |
|
7 |
Gomphrena serrata
L. |
Amaranthaceae |
Prostrate Gomphrena |
South America |
Up to 1,000 m |
₊ |
|
|
₊ |
|
|
2 |
1 |
|
8 |
Catharanthus roseus (L.) G.Don. |
Apocynaceae |
Madagascar Periwinkle, Rosy
Periwinkle |
Tropical America |
Up to 1,800 m |
₊ |
|
|
₊ |
|
₊ |
3 |
1 |
|
9 |
Cascabela thevetia (L.) Lippold |
Apocynaceae |
Yellow Oleander |
Peru |
Up to 1,400 m |
|
|
|
₊ |
|
|
1 |
1 |
|
10 |
Pistia stratiotes L. |
Araceae |
Water Lettuce |
South America |
Up to 1,400 m |
|
|
|
|
₊ |
₊ |
2 |
1,2 |
|
11 |
Asclepias curassavica L. |
Asclepiadaceae |
Scarlet Milkweed |
Tropical America |
>500 m |
₊ |
|
|
|
₊ |
₊ |
3 |
1,2 |
|
12 |
Acanthospermum hispidum DC. |
Asteraceae |
Starbur, Goat's head,
Bristly Starbur |
Brazil |
Up to 1,000 m |
₊ |
₊ |
|
₊ |
|
|
3 |
1,2 |
|
14 |
Acmella radicans (Jacq.) R.K.Jansen |
Asteraceae |
White Spot flower |
Southern America |
Up to 1,000 m |
₊ |
|
|
|
₊ |
|
2 |
3 |
|
15 |
Ageratina adenophora (Spreng.) R.M.King & H.Rob. |
Asteraceae |
Crofton weed |
Mexico |
300–2,500 m |
|
₊ |
₊ |
₊ |
|
₊ |
4 |
1 |
|
16 |
Ageratum conyzoides
L. |
Asteraceae |
Goat weed, White weed |
South America |
Up to 2,000 m |
₊ |
₊ |
₊ |
₊ |
|
₊ |
5 |
1,3 |
|
17 |
Ageratum houstonianum
Mill. |
Asteraceae |
Blue weed |
Central America |
Up to 1,300 m |
₊ |
₊ |
₊ |
₊ |
|
₊ |
5 |
1 |
|
18 |
Ambrosia artemisiifolia
L. |
Asteraceae |
Common Ragweed |
North America |
Up to 1,000 m |
|
₊ |
₊ |
₊ |
|
|
3 |
1,2 |
|
19 |
Anthemis cotula L. |
Asteraceae |
Stinking Chamomile, Wild
Chamomile |
Temperate Eurasia |
Up to 1,600 m |
|
|
₊ |
₊ |
|
|
2 |
1 |
|
20 |
Bidens biternata (Lour.) Merr. & Sherff. |
Asteraceae |
Spanish needles |
America |
Up to 2,000 m |
₊ |
₊ |
₊ |
₊ |
|
|
4 |
1,3 |
|
21 |
Bidens pilosa L. |
Asteraceae |
Beggar's tick or Spanish needle |
America |
Up to 3,600 m |
₊ |
₊ |
₊ |
₊ |
|
|
4 |
1 |
|
22 |
Chromolaena odorata (L.) R.M.King
& H.Rob. |
Asteraceae |
Siam weed |
North America |
Up to 1,000 m |
₊ |
₊ |
|
₊ |
|
₊ |
4 |
1 |
|
23 |
Crassocephalum crepidioides (Benth)
S.Moore |
Asteraceae |
Fireweed |
Tropical Africa |
Up to 1,800 m |
|
|
|
|
₊ |
₊ |
2 |
1 |
|
24 |
Erigeron karvinskianus
DC. |
Asteraceae |
Australian Daisy |
Mexico |
1,000–2,000 m |
|
|
₊ |
₊ |
|
|
2 |
1 |
|
25 |
Flaveria trinervia (Spreng) C.Mohr |
Asteraceae |
Sprengel |
Central America |
Up to 2,000 m |
₊ |
|
|
₊ |
|
|
2 |
4 |
|
26 |
Galinsoga parviflora Cav. |
Asteraceae |
Gallant soldier |
Tropical America |
Up to 2,000 m |
₊ |
₊ |
|
₊ |
₊ |
|
4 |
1 |
|
27 |
Gamochaeta coarctata (Willd.) Kerguélen |
Asteraceae |
Grey everlasting |
South America |
1800–2,200 m |
|
₊ |
₊ |
₊ |
|
|
4 |
1 |
|
28 |
Gamochaeta purpurea (L.) Cabrera |
Asteraceae |
Purple Cudweed |
North America |
500–2,600 m |
|
₊ |
₊ |
|
|
|
3 |
1 |
|
29 |
Mikania micrantha
Kunth |
Asteraceae |
Mile-a-minute |
North, Central and South
America |
Up to 1,000 m |
₊ |
₊ |
|
₊ |
|
|
3 |
1 |
|
30 |
Parthenium hysterophorus
L. |
Asteraceae |
Carrot grass, Congress grass |
America |
Up to 1,400 m |
₊ |
₊ |
₊ |
₊ |
|
|
3 |
1,4 |
|
31 |
Synedrella nodiflora (L). Gaertn. |
Asteraceae |
Cinderella weed |
West Indies |
Up to 800 m |
₊ |
|
|
₊ |
|
|
2 |
1 |
|
32 |
Tithonia diversifolia (Hemsl.)
A.Gray |
Asteraceae |
Mexican Sunflower |
South America |
500–1,900 m |
₊ |
₊ |
|
₊ |
|
|
3 |
1 |
|
33 |
Tridax procumbens L. |
Asteraceae |
Coat button |
Mexico |
Up to 1,000 m |
₊ |
|
|
₊ |
|
|
3 |
1 |
|
34 |
Cardamine trichocarpa Hochst. ex A.Rich. |
Brassicaceae |
Bittercress |
Temperate Eurasia |
>1,200 m |
|
|
₊ |
₊ |
|
|
3 |
4 |
|
35 |
Lepidium didymum L. |
Brassicaceae |
Swine Cress |
Tropical America |
Up to 2,200 m |
₊ |
|
|
₊ |
|
|
2 |
1,5 |
|
36 |
Opuntia tuna (L.) Mill. |
Cactaceae |
Spiny Pest Pear |
Mexico |
50– 900 m |
₊ |
|
|
|
|
|
1 |
1,2 |
|
37 |
Opuntia stricta
(Haw.) Haw.
|
Cactaceae |
Pricky Pear |
Mexico |
300–1200 m |
₊ |
|
|
|
|
|
1 |
1 |
|
38 |
Senna alata
(L.) Roxb. |
Caesalpiniaceae |
Christmas Candle, Candle brush |
South America |
Up to 1,200 m |
₊ |
|
|
|
|
|
1 |
1 |
|
39 |
Senna occidentalis
(L.) Link |
Caesalpiniaceae |
Septic weed, Coffee weed |
South America |
Up to 1,500 m |
₊ |
|
|
|
|
|
1 |
1 |
|
40 |
Casuarina equisetifolia
L. |
Casuarinaceae |
Australian Pine |
Australia, Malaysia &
Pacific Islands |
Up to 1,500 m |
₊ |
|
|
₊ |
|
|
2 |
1 |
|
41 |
Ipomoea carnea
Jacq. |
Convolvulaceae |
Pink Morning Glory |
South America |
Up to 1,000 m |
₊ |
|
|
|
₊ |
₊ |
3 |
1,6 |
|
42 |
Ipomoea indica
(Burm.) Merr. |
Convolvulaceae |
Blue Dawn Flower |
South America |
Up to 1,500 m |
|
|
₊ |
₊ |
|
|
2 |
1 |
|
43 |
Kalanchoe delagoensis
Eckl. & Zeyh. |
Crassulaceae |
Chandelier plant |
Madagascar |
Up to 1,000 m |
₊ |
|
|
|
₊ |
₊ |
3 |
1 |
|
44 |
Chrozophora plicata (Vahl) A. Juss. ex Spreng. |
Euphorbiaceae |
_ |
Tropical Africa |
Up to 1,000 m |
₊ |
|
|
|
|
|
1 |
2 |
|
45 |
Croton bonplandianus
Baill. |
Euphorbiaceae |
Railway weed |
South America |
Up to 900 m |
₊ |
|
|
|
|
|
1 |
4 |
|
46 |
Euphorbia cyathophora
Murray |
Euphorbiaceae |
Painted Poinsettia |
North and South America |
Up to 1,000 m |
₊ |
|
|
|
|
|
1 |
1,6 |
|
47 |
Euphorbia helioscopia
L. |
Euphorbiaceae |
Sun Spurge |
West Asia |
1000–2000 m |
₊ |
₊ |
|
|
|
|
2 |
1,4 |
|
48 |
Euphorbia hirta
L. |
Euphorbiaceae |
Common Spurge |
Tropical America |
Up to 1,400 m |
₊ |
|
|
₊ |
|
|
2 |
1,4 |
|
49 |
Aeschynomene americana L. |
Fabaceae |
Shyleaf, Common Aeschynomene |
Tropical America |
Up to 1,000 m |
₊ |
|
|
|
₊ |
|
2 |
1 |
|
50 |
Aeschynomene indica L. |
Fabaceae |
Indian Joint Vetch |
North and Central America |
Up to plains to 2,000 m |
₊ |
₊ |
|
|
₊ |
|
3 |
1 |
|
51 |
Cytisus scoparius (L.) Link |
Fabaceae |
Scotch Broom |
Western and Central Europe |
1,800–2,400 m |
|
|
₊ |
₊ |
|
|
2 |
1 |
|
52 |
Prosopis juliflora
(Sw.) DC. |
Fabaceae |
Algaroba, Mesquite |
South America |
Up to 1,000 m |
₊ |
|
|
|
|
|
1 |
1 |
|
53 |
Stylosanthes hamata (L.) Taub. |
Fabaceae |
Caribbean Stylo |
Central America |
Up to 1,800 m |
|
|
₊ |
₊ |
₊ |
|
3 |
1,6 |
|
54 |
Ulex europaeus L. |
Fabaceae |
Gorse |
Western Europe |
1,800–2,000 m |
|
|
₊ |
₊ |
₊ |
|
3 |
1 |
|
55 |
Miconia crenata (Vahl) Michelang. |
Melastomataceae |
Soapbush |
Tropical America |
Up to 1,200 m |
|
₊ |
|
₊ |
|
|
2 |
1 |
|
56 |
Acacia mearnsii
De Wild. |
Mimosaceae |
Black Wattle |
Australia |
>1,600 m |
|
₊ |
₊ |
₊ |
₊ |
|
4 |
1 |
|
57 |
Desmanthus virgatus (L.) Willd. |
Mimosaceae |
Hedge Lucerne |
Tropical America |
Up to 1,000 m |
₊ |
|
|
|
|
|
1 |
1 |
|
58 |
Leucaena latisiliqua (L.) Gillis. |
Mimosaceae |
Horse Tamarind |
Tropical America |
Up to 150 m |
₊ |
|
|
₊ |
|
|
2 |
1 |
|
59 |
Mimosa pudica
L. |
Mimosaceae |
Touch-me-not |
South America |
Up to 1,800 m |
₊ |
₊ |
|
|
₊ |
|
3 |
1 |
|
60 |
Vachellia farnesiana (L.) Wight & Arn. |
Mimosaceae |
Needle bush, Sweet Acacia |
Tropical America |
Up to 1,000 m |
₊ |
|
|
|
|
|
1 |
1 |
|
61 |
Broussonetia papyrifera (L.) Vent. |
Moraceae |
Paper Mulberry |
East Asia |
Up to 1,000 m |
₊ |
|
|
|
|
|
1 |
1 |
|
62 |
Argemone mexicana L. |
Papaveraceae |
Mexican Prickly Poppy |
South America |
Up to 1,000 m |
₊ |
|
|
₊ |
|
|
2 |
1 |
|
63 |
Passiflora foetida L. |
Passifloraceae |
Stinking Passionflower |
Brazil & West Indies |
Up to 1,800 m |
₊ |
₊ |
|
|
|
|
2 |
1 |
|
64 |
Passiflora mollissima L.H.Bailey |
Passifloraceae |
Banana Passionfruit |
Tropical South America |
Up to 1,800 m |
₊ |
₊ |
|
₊ |
|
|
3 |
1 |
|
65 |
Phalaris minor Retz. |
Poaceae |
Little-seeded Canary grass |
Mediterranean region |
Up to 1,800 m |
₊ |
₊ |
|
|
₊ |
|
3 |
1,2 |
|
66 |
Phragmites australis
(Cav.) Trin. ex Steud. |
Poaceae |
Common Reed |
Temperate Eurasia |
Up to 1,000 m |
₊ |
₊ |
|
|
₊ |
₊ |
4 |
1,2 |
|
67 |
Polypogon monspeliensis (L.) Desf. |
Poaceae |
Rabbitfoot grass |
Temperate Eurasia |
Up to 1,000 m |
|
|
₊ |
|
₊ |
|
2 |
1 |
|
68 |
Chloris barbata Sw. |
Poaceae |
Swollen windmill grass |
Tropical America & Africa |
Up to 2,000 m |
₊ |
|
|
|
₊ |
|
2 |
1 |
|
69 |
Urochloa panicoides P. Beauv. |
Poaceae |
Liverseed grass |
Tropical America |
Up to 1,700 m |
₊ |
|
|
|
|
|
1 |
1 |
|
70 |
Antigonon leptopus Hook. & Arn. |
Polygonaceae |
Coral vine |
South America |
Up to 1,000 m |
₊ |
|
|
|
|
|
1 |
1 |
|
71 |
Pontederia crassipes Mart. |
Pontederiaceae |
Water Hyacinth |
South America |
Up to 2,000 m |
|
|
|
|
₊ |
₊ |
2 |
1,2 |
|
72 |
Monochoria vaginalis K.B.Presl. |
Pontederiaceae |
Pickerel weed |
Southeast Asia |
Up to 1,200 m |
|
|
|
|
₊ |
₊ |
2 |
1 |
|
73 |
Calceolaria mexicana
Benth. |
Scrophulariaceae |
Ladies purse |
Mexico |
1800–2,000 m |
|
|
₊ |
₊ |
₊ |
|
3 |
2,4 |
|
74 |
Ailanthus altissima
(Miller) Swingle |
Simaroubaceae |
Tree of heaven |
China |
Up to 2,000 m |
₊ |
|
|
|
|
|
1 |
1 |
|
75 |
Cestrum aurantiacum
Lindl. |
Solanaceae |
Orange Jasmine |
North and South America |
1,200–2,600 m |
|
₊ |
₊ |
₊ |
|
|
3 |
1 |
|
76 |
Datura innoxia
Mill. |
Solanaceae |
Downy Thorn-apple |
Tropical and subtropical
America |
Up to 1,800 m |
₊ |
₊ |
|
|
|
|
2 |
1 |
|
77 |
Datura stramonium L. |
Solanaceae |
Common Thorn-apple |
Tropical America |
Up to 2,700 m |
₊ |
₊ |
|
₊ |
|
₊ |
4 |
1 |
|
78 |
Solanum mauritianum
Scop. |
Solanaceae |
Tobacco tree |
South America |
Up to 2,200 m |
|
₊ |
₊ |
₊ |
|
₊ |
4 |
1,2 |
|
79 |
Solanum seaforthianum
Andrews |
Solanaceae |
Brazilian Nightshade |
Tropical America |
1,300–1,500 m |
₊ |
|
|
|
|
|
1 |
1 |
|
80 |
Lantana camara
L. |
Verbenaceae |
Big Sage |
Central and South America |
Up to 2,000 m |
₊ |
₊ |
₊ |
₊ |
|
₊ |
5 |
1,4 |
|
81 |
Stachytarpheta jamaicensis (L.) Vahl. |
Verbenaceae |
Jamaican Blue Spike |
South America |
Up to 800 m |
₊ |
₊ |
|
|
|
|
2 |
1 |
Ref: 1—www.cabidigitallibrary.org
| 2—efloraofindia.com | 3—flowersofindia.net | 4—https://indiabiodiversity.org
|
5—https://wgbis.ces.iisc.ac.in/biodiversity/sahyadri_enews/newsletter/issue42/bibliography/The-alien-flora-of-Kashmir-Himalaya.pdf
| 6—https://www.gbif.org
Annexure 2. Shortlisted species.
|
|
Name of the species |
Criterion 11 |
Criterion 21 |
Criterion 31 |
Reference2 |
|
1 |
Acacia mearnsii
De Wild. |
Yes |
Yes |
Yes |
1 |
|
2 |
Acanthospermum hispidum DC. |
Yes |
Yes |
Yes |
1 |
|
3 |
Ageratina adenophora (Spreng.) R.M.King & H.Rob. |
Yes |
Yes |
Yes |
1 |
|
4 |
Ageratum conyzoides
L. |
Yes |
Yes |
Yes |
1 |
|
5 |
Ageratum houstonianum
Mill. |
Yes |
Yes |
Yes |
1 |
|
6 |
Alternanthera philoxeroides (Mart.) Griseb. |
Yes |
Yes |
Yes |
1 |
|
7 |
Alternanthera sessilis (L.) R.Br. ex DC. |
Yes |
Yes |
Yes |
1 |
|
8 |
Argemone mexicana L. |
Yes |
Yes |
Yes |
1 |
|
9 |
Asclepias curassavica R.Br. |
Yes |
Yes |
Yes |
1 |
|
10 |
Bidens pilosa L. |
Yes |
Yes |
Yes |
1 |
|
11 |
Cestrum aurantiacum
Lindl. |
Yes |
Yes |
Yes |
1 |
|
12 |
Chromolaena odorata (L.) King & H.Rob. |
Yes |
Yes |
Yes |
1 |
|
13 |
Cytisus scoparius (L.) Link |
Yes |
Yes, spread widely |
High altitudes |
1 |
|
14 |
Datura innoxia
Mill. |
Yes |
Yes |
Yes |
1 |
|
15 |
Pontederia crassipes Mart. |
Yes |
Yes |
Yes |
1 |
|
16 |
Gamochaeta purpurea (L.) Cabrera |
Yes |
Yes |
Yes |
1 |
|
17 |
Kalanchoe delagoensis
Eckl. & Zeyh. |
Yes |
Yes |
Yes |
1 |
|
18 |
Lantana camara
L. |
Yes |
Yes |
Yes |
1 |
|
19 |
Mikania micrantha
Kunth |
Yes |
Yes |
Yes |
1 |
|
20 |
Opuntia tuna (L.) Mill. |
Yes |
Yes |
Yes |
1 |
|
21 |
Opuntia stricta
Haw. |
Yes |
Yes |
Yes |
1 |
|
22 |
Parthenium hysterophorus
L. |
Yes |
Yes |
Yes |
1 |
|
23 |
Passiflora mollissima L.H.Bailey |
Yes |
Yes |
Yes |
1 |
|
24 |
Phragmites australis
(Cav.) Trin. ex Steud. |
Yes |
Yes |
Yes |
1 |
|
25 |
Pistia stratiotes L. |
Yes |
Yes |
Yes |
1 |
|
26 |
Prosopis juliflora
(Sw.) DC. |
Yes |
Yes |
Yes |
1 |
|
27 |
Senna alata
(L.) Roxb. |
Yes |
Yes |
Yes |
1 |
|
28 |
Senna occidentalis
(L.) Link |
Yes |
Yes |
Yes |
1 |
|
29 |
Solanum mauritianum
Scop. |
Yes |
Yes |
Yes |
1 |
|
30 |
Synedrella nodiflora L. Gaertn. |
Yes |
Yes |
Yes |
1 |
|
31 |
Cascabela thevetia (L.) Lippold |
Yes |
Yes |
Yes |
1 |
|
32 |
Tithonia diversifolia (Hemsl.)
A.Gray |
Yes |
Yes |
Yes |
1 |
|
33 |
Tridax procumbens L. |
Yes |
Yes |
Yes |
1 |
|
34 |
Ulex europaeus L. |
Yes |
Yes |
Yes |
1 |
1 Note on criteria:
Criterion 1—Species that are well
known in the landscapes (a measure of the species’ impacts and abundance) |
Criterion 2— Species that have
spread into multiple habitats (a measure of the species’ local abundance) |
Criterion 3—Species that occur
over more than one altitudinal zone (a measure of the species’ spread).
2 References: 1—Personal
communication, 18 January 2017: V. Anita, H. Ankila,
B. Milind, Samuel Thomas, Shiny M. Rehel
(corroborated by observation of workshop participants).
Annexure 3. Final list of species for mapping
invasive alien species in the Nilgiris.
|
|
Name of the species |
Habit |
Common name |
|
1 |
Acacia mearnsii
De Wild. |
Tree |
Black Wattle |
|
2 |
Ageratina adenophora (Spreng.) R.M.King & H.Rob. |
Herb |
Crofton Weed |
|
3 |
Ageratum conyzoides
L. |
Herb |
Goat Weed |
|
4 |
Ageratum houstonianum
Mill. |
Herb |
Floss Flower |
|
5 |
Alternanthera philoxeroides (Mart.) Griseb. |
Herb |
Alligator Weed |
|
6 |
Asclepias curassavica L. |
Herb |
Milk Weed |
|
7 |
Bidens pilosa L. |
Herb |
Blackjack |
|
8 |
Cestrum aurantiacum
Lindl. |
Shrub |
Orange Cestrum |
|
9 |
Chromolaena odorata (L.) R.M.King
& H.Rob. |
Herb |
Siam Weed |
|
10 |
Cytisus scoparius (L.) Link |
Herb |
Scotch Broom |
|
11 |
Datura innoxia
Mill. |
Shrub |
Downy Thorn-apple |
|
12 |
Pontederia crassipes Mart. |
Herb |
Water Hyacinth |
|
13 |
Gamochaeta purpurea (L.) Cabrera |
Herb |
Purple Spoonleaf
everlasting |
|
14 |
Lantana camara
L. |
Shrub |
Wild Sage |
|
15 |
Mikania micrantha
Kunth |
Shrub |
Bitter Vine |
|
16 |
Opuntia tuna (L.) Mill. |
Shrub |
Prickly Pear |
|
17 |
Parthenium hysterophorus
L. |
Shrub |
Parthenium |
|
18 |
Passiflora mollissima L.M.Bailey |
Climber |
Banana Passion |
|
19 |
Phragmites australis
(Cav.) Trin. ex Steud. |
Grass |
Common Reed |
|
20 |
Prosopis juliflora
(Sw.) DC. |
Tree |
Mesquite |
|
21 |
Senna spectabilis
(DC.) H.S.Irwin & Barneby |
Tree |
American Cassia |
|
22 |
Solanum mauritianum
Scop. |
Shrub |
Bugweed |
|
23 |
Pistia stratiotes L. |
Herb |
Water Lettuce |
|
24 |
Ulex europaeus L. |
Herb |
Common Gorse |
|
25 |
Pennisetum clandestinum Hochst. ex Chiov |
Grass |
Kikuyu Grass |
|
26 |
Polygonum polystachyum
Wall. ex Meisn. |
Herb |
Himalayan Knotweed |