ArticlePDF Available

Invasion meltdown and burgeoning threats of invasive fish species in inland waters of India in the era of climate change

Authors:

Abstract

Cyprinus carpio, Oreochromis niloticus and Clarias gariepinus are the most abundantly captured invasive fish species in the mid-stretch of the Ganga river. Fish yield and biomass data based on mean abundance by weight was calculated using algorithms and spatio-temporal population dynamics model for future prediction of these invasive fish species. Temporal biomass forecast based on mean abundance by wieght for the period from 2020 to 2029 was determined. The findings of this study predicted fish yield of 176 ±16.33 kg km-1 day-1 C. carpio and 55.43 ± 6.4 kg km-1 day-1 O. niloticus during 2029 which might result into 117.87% and 116.9% rise in temporal biomass of Common Carp and Tilapia respectively in a decade’s time while 139.2% rise in temporal biomass was predicted for the invasive African catfish. The yield of invasive Common Carp, Tilapia and African Catfish was correlated with rainfall and temperature data using ANOVA and we found that variance was F=1.36; p=0.263 for C. carpio; F=1.60; p=0.326 for O. niloticus and F=1.63; p=0.101 for C. gariepinus, indicating that variance was very close for Tilapia and African Catfish. The observed values of variance indicated that climatic changes had more impact to these two species than to the Common Carp. The concrete and forecast values were calculated considering 95% lower and upper level of confidence, which was significant (p<0.05) and the annual regression was found to be p<0.464, p<0.419 and p<0.499 for C. carpio, O. niloticus and C. gariepinus, respectively. Further, interactive performance of invaded C. carpio, O. niloticus and C. gariepinus was also assessed for understanding invasion meltdown. The results of mean abundance by weight based yield forecast of invaded Tilapia, Common Carp and African Catfish for the period of 2020 to 2029 suggest a stable production in the Ganga River in years to come. It also manifests a positive pattern of invasion in the times of climate change displaying invasion meltdown. This suggests increased pressures of fish invasions on temporal and spatial scales, and imposing new management challenges for freshwater ecosystems.
18
Aquatic Ecosystem Health & Management, 24(3): 18–27, 2021. Copyright © 2021 Aquatic Ecosystem Health & Management Society.
ISSN: 1463-4988 print / 1539-4077 online. DOI: 10.14321/aehm.024.03.04
Introduction
Freshwater fish form a key component of
invasive alien fauna in many countries around the
world including India, and several regions have
fish communities with high proportions of non-
native species (Leprieur et al. 2008; Singh and
Lakra, 2011; Singh et al., 2013). In the Ganga river,
many invasive fish species have been reported and
are contributing to the fishery (Singh et al., 2013).
Introduced fish invasions in the time of climate
change have been reported to represent key threats
Invasion meltdown and burgeoning threats of invasive
fish species in inland waters of India in the era of climate
change
Atul K. Singh* and Sharad C Srivastava
National Bureau of Fish Genetic Resources, Canal Ring Road, P.O. Dilkusha
Lucknow-226002 (Uttar Pradesh), India
*Corresponding author: aksingh56@rediffmail.com; singhatk@gmail.com
Cyprinus carpio, Oreochromis niloticus and Clarias gariepinus are the most abundantly captured
invasive sh species in the mid-stretch of the Ganga river. Fish yield and biomass data based on mean
abundance by weight was calculated using algorithms and spatio-temporal population dynamics model
for future prediction of these invasive sh species. Temporal biomass forecast based on mean abundance
by wieght for the period from 2020 to 2029 was determined. The ndings of this study predicted sh yield
of 176 ±16.33 kg km-1 day-1 C. carpio and 55.43 ± 6.4 kg km-1 day-1 O. niloticus during 2029 which might
result into 117.87% and 116.9% rise in temporal biomass of Common Carp and Tilapia respectively in a
decade’s time while 139.2% rise in temporal biomass was predicted for the invasive African catsh. The
yield of invasive Common Carp, Tilapia and African Catsh was correlated with rainfall and temperature
data using ANOVA and we found that variance was F=1.36; p=0.263 for C. carpio; F=1.60; p=0.326 for
O. niloticus and F=1.63; p=0.101 for C. gariepinus, indicating that variance was very close for Tilapia
and African Catsh. The observed values of variance indicated that climatic changes had more impact to
these two species than to the Common Carp. The concrete and forecast values were calculated considering
95% lower and upper level of condence, which was signicant (p<0.05) and the annual regression was
found to be p<0.464, p<0.419 and p<0.499 for C. carpio, O. niloticus and C. gariepinus, respectively.
Further, interactive performance of invaded C. carpio, O. niloticus and C. gariepinus was also assessed
for understanding invasion meltdown. The results of mean abundance by weight based yield forecast
of invaded Tilapia, Common Carp and African Catsh for the period of 2020 to 2029 suggest a stable
production in the Ganga River in years to come. It also manifests a positive pattern of invasion in the
times of climate change displaying invasion meltdown. This suggests increased pressures of sh invasions
on temporal and spatial scales, and imposing new management challenges for freshwater ecosystems.
Keywords: Ganga river, climatic factors, temporal biomass
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27 19
to global biodiversity (Galil et al., 2008; Rolls et
al., 2017). Invasion of introduced fish species and
their effects on habitats has emerged as a major
threat to ecosystems around the globe in general
and in India in particular (Singh and Lakra, 2011;
Singh et al., 2013; Fletcher et al., 2016). Although
invasive species possess many attributes that can
explain its ability to spread and survive even in
new habitats and harsh environments, no study has
identified processes that might explain its restricted
pattern of superabundance. A few researchers have
tried to estimate invasive species biomass and
abundance on the basis of the mean abundance
by weight (Dominguez et al., 2020; Singh and
Srivastava, 2020). Several models estimating
spatial and temporal variation in population density
are increasingly used to track shifts in population
distribution subject to environmental and climatic
changes (Harsch et al. 2014; Thorson et al., 2017).
In recent times, increased global temperatures
have been reported to help invasive species establish
themselves in newer aquatic ecosystems (Arnaud et
al., 2021). Rivers and streams have been reported to
get warmed during the past few decades, and stream
and water temperatures were projected to increase
further in future as warmer climates. Climate not
only has an impact on physical characteristics on
surface waters, but also is a master variable for
ecologically important chemical processes (Galil et
al., 2008; Auffhammer et al 2012; Jayaraman and
Murari, 2014). Invasive species might cause habitat
modification, extinctions of endemic species, affect
human health, and therefore endanger enormous
economic costs (Singh and Lakra, 2011; Singh et
al., 2013; Singh et al., 2014; Hanley and Michaela,
2019). In current time, unsustainable harvesting
of natural stock of fishes especially from inland
waters owing to invasion of introduced fish species
led habitat degradation of riverine ecosystem and
emerging conservation issues in the tropics, which
has resulted in the stock decline of important local
fish species, (Singh et al. 2013; Panlasigui et al.,
2018; Mondal and Bhat 2020). Climate variables,
namely temperature, precipitation, and humidity
may have significant long-term implications on
water quality and fisheries with special reference to
fish invasions (Auffhammer et al 2012; Jayaraman
and Murari, 2014).
In this study, we investigated how invasive
fish species will flourish on temporal scale under
the influence of climate change in future. By
extrapolating the ten years data (2010-2019) on the
yield and biomass for three invasive fish namely
the common carp, tilapia and African catfish from
the mid-stream of the Ganga river, we attempted
to forecast temporal biomass changes for the
next decade i.e., from 2020 to 2029 using spatio-
temporal population dynamics model for future
prediction. Further, we also tested the invasion
meltdown hypotheses that the presence of a second
invading species enhanced the abundance and
potential for further invasion by another non-native
species causing aggravated detrimental impacts to
indigenous species in terms of their abundance.
Materials and Methods
Fish catch data and biomass
Data on the catch of non-native species the
common carp, tilapia and African catfish was
collected from the mid-stretch of the Ganga
river through regular fishing exercise made by
fishermen at different fish landing areas of bridge
area in Kanpur, Mehdi ghat in Kannauj, Shuklaganj
in Unnao, Daraganj in Prayagraj, Adalhat in
Mirzapur, Saraimohana in Varanasi, Dadri ghat
in Ghazipur and Ganga ghat in Ballia districts of
Uttar Pradesh state of India by using mostly boats,
gillnets, cast nets and occasionally drag net (Figure
1). The catch data for three invasive fish namely
the Cyprinus carpio, Oreochromis niloticus and
Clarias gariepinus were collected from different
locations on monthly basis for the study period
from 2010 to 2019. Catch per unit effort (CPUE)
was calculated for each study location following
the method described by Bucol et al. (2017).
Figure 1. Figure showing the sampling locations in the Ganga
river in Uttar Pradesh, India.
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27
20
The CPUE was further converted as biomass
percentage (Pi) of the three abundantly captured C.
carpio, O.niloticus and C. gariepinus non-native
fish at individual study location as per formula Pi
= Wi/Wt, where Wi was the weight of non-native
fish species; Wt was the total weight from all
catches. The biomass obtained from each location
was then pooled for calculating total biomass (Pf)
percentage of fish from all the studied locations as
per formula: Pf = Pi1 + Pi2 + Pi3 + Pi4 + Pin over
the years (ArchMiller et al., 2018) and the time
rate change of non-native fish biomass during the
period of 2010 to 2019 was calculated as:
dP/dt P or dP/dt = aP the solution was P = P0 eat
Where P was the biomass at time t and P0 was the
initial biomass.
The predictive biomass was calculated
as per described methodology (Okubo et al.,
2017). Mean abundance by weight (MAW) was
estimated (Leeseberg and Keeley, 2014; Singh and
Srivastava, 2020). The changes in MAW were then
extrapolated as biomass for the period from 2020
to 2029 (Laplanchea et al., 2018). The sight ability
model-fit to detection/non-detection data from
marked population of the most invaded non-native
invasive C. carpio, O. niloticus and C. gariepinus
were then extrapolated for the next ten-year decade,
i.e. 2020 to 2029 (Singh and Srivastava, 2020).
For a given predictor p among n predictors,
the weight was calculated using the following
equation:
Weight p =
In this process, data were fitted for all years
tfitted {tinitial ,…, tfinal}, and then average estimated
abundance and weight for all studied areas was
used to predict density d (s, t) for all locations
during forecast years tforecast {tfinal + 1, tfinal + 2, tfinal +
3……n}. Finally, population weight prediction was
used to calculate the centroid of the population’s
distribution:
Z(t) = Σns
s=1Z(sa(s) × d(s,t)
Σns
s=1(a(s) × d(s,t)
Where a (s) was the area associated with each
location s, and z(s) was the measure of location
(km). The biomass data in terms of weight (g)
was pooled for entire stretch of 450 km of the
Ganga river. The future values of standard errors
followed by probability values were calculated.
The changes in mean abundance by weight (MAW)
was calculated as biomass at ΔYM AW (Δt / tfinal) for
forecasting temporal biomass for the year 2020 Δt
to 2029 as year tfinal:
ΔYMAW (Δt/ tfinal) = Y (tfinal + Δt) –Y (tfinal)
Where Δt {2020-29}, the change in centroid was
ΔY t/tfinal) over Δt and the forecasting year for
calculating data through years 2020 to 2029 was
tfinal. The forecasted centroid as YCE (tforecast/ tfinal) in
year tforecast was done using the data through tfinal and
the growth model:
ΔY CE (Δt/tfina) l = YCE (tfinal + Δt/tfinal) – YCE (tfinal/ tfinal)
The variance are explained as R2t) = 1–Vt),
a model performing as well as the persistence
forecast which had V t) = 1 and R2t) = 0,
while the model with R2t) > 0 outperforms the
persistence forecast while the model with R2t) < 0
had degraded performance relative to a persistence
forecast (Draper and Smith, 1998).
Climate monitoring
Water temperature changes was determined on
quarterly and on annual basis for the period from
2009 to 2019 using digital thermometer so as to
capture the changes/ modifications/ transformations
in the water quality indicators. The rainfall data
(1989-2019) of the mid-stretch in the Ganga river
was collected from the India Meteorological
Department (IMD) and district wise available
information were used in our data analysis.
Statistics
All data were presented as mean ± SE. Field
data obtained from different study locations
were subjected to one-way analysis of variance
(ANOVA) using the Statistical Package for
the Social Sciences (SPSS), version 8.1. The
correlation coefficients between the water quality
indicators from different locations were calculated
by Pearson correlation analysis. Parameters were
further analyzed statistically at 5% significance
level. The concrete and forecast values were
calculated considering 95% lower and upper level
of confidence; and the annual regression was
calculated (Singh and Srivastava, 2020).
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27 21
Results
Water temperature data were collected and
presented over the years in the mid-stretch of the
Ganga river covering from Kanpur to downstream
Ballia. The annual mean minimum water
temperature in the mid-stretch of the Ganga river
was low in 2012, 2014 and 2018 and high during
2011, 2013 and 2019. However, the annual mean
temperature increased from 0.9 to 1.88ºC over the
years (Figure 2). The regression value showed that
the relationship between the low and high for the
base year 2010 to final year 2019 were 0.048 and
0.076 respectively. Temperature was found directly
related to rainfall, with an increase in temperature
at the end of the winter months i.e. January-
February through spring (October-November) and
finally to summer, i.e. the months of April-May.
This increase in temperature was not linear, but
there was a sudden temperature increase within a
short period of time.
The annual rainfall data changes were
synthesized from available data from IMD. The
proportion of annual total rainfall occurring in
the monsoon months (May-August) was 69.42%
during 1989-98 which gradually decreased to
65.4% during 1910-19 and further decreased during
1989-98 to 25.28%. However, it increased in post
monsoon months (September-December) from
28.32% during 2010-19 (Figure 3). Temperature
and rainfall were understood as important
environmental factor that triggered the maturation
of brood fish expected to have different stages of
maturity.
Common catches of non-native C. carpio
contributed 47.46 % to 58.38% during study
period; O. niloticus 29.52% to 32.89% and C.
gariepinus 1.52 to 8.4% in the mid-stretch of the
Ganga river. The size range of captured Cyprinus
carpio was 13.5 to 52.4 cm in length and 150 to
1680 g in weight; Oreochromis niloticus 8.6 to 32.8
cm in length and 35g to 950g in weight; Clarias
gariepinus 11.7 to 50.72 cm in length and 170
to 838g in weight. The O. niloticus appeared for
the first time during 2003 in the Ganga river at
Allahabad followed by common carp during 2004
and later African catfish appeared for the first time
during 2011 on the same locations. The appearance
of Tilapia and Common Carp synergistically and
gradually increased over the years, while the third
invasive fish African Catfish emerged during
2011(Figure 4). The yield of invasive Common
Carp, Tilapia and African Catfish was correlated
with rainfall and temperature data using ANOVA;
we found that variance was F=1.36; p=0.263 for
C. carpio; F=1.60; p=0.326 for O. niloticus and
F=1.63; p=0.101 for C. gariepinus. The calculated
variance value was very close for Tilapia and
African Catfish indicating that climatic changes
impacted these two species more than the Common
Carp.
Figure 2. Annual trend in mean minimum and maximum water temperature at mid-stretch of the Ganga river during 2010-2019.
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27
22
Fish yield calculation based on MAW for C.
carpio was found to consistently increase (p < 0.05)
over the years from 2010 to 2019 and the calculated
yearly values were 113.65, 127.54, 139.08, 150.99,
158.67, 174.54, 192.22, 209.06, 219.92 and 235.83
kg km-1 day-1 (Figure 5). The increase in MAW
based yield of C. carpio was consistent and highly
significant (p< 0.001) particularly during the
period from 2016 to 2018 as compared to the base
year value in 2010. In case of O. nolitcus, there
was again a consistent and significant (p< 0.05)
increase of MAW based fish yield over the years
from 2010 to 2019 and the recorded values were
57.51, 68.02, 77.20, 83.37, 90.05, 100.52, 133.58,
148.13, 151.74 and 151.13 kg km-1 day-1 (Figure 6).
However, the increase in yield of O. niloticus was
very noticeable and highly significant (p< 0.001)
during the period from 2013 to 2018 as compared to
the base year value in 2010. The C. gariepinus was
observed in mid-stream of the Ganga river during
2011 which consistently increased year after year.
The recorded yield for the year from 2011 to 2019
were 2.41, 6.73, 14.64, 23.81, 27.45, 33.4, 36.45,
36.96 and 39.82 kg km-1 day-1 respectively (Figure
7). However, the increase in MAW based yield of
C. gariepinus was significantly observed during
the period from 2013 to 2019 as compared to the
base year value in 2011 when it first appeared. The
evaluated temporal predictive values for forecasted
years (2020 to 2029) based on MAW values were
plotted using spatio-temporal population dynamics
model and the observations are presented (Fig. 5, 6,
7). The calculation for MAW based concrete yield
showed that the average value was 113.65±12.6 kg
km-1 day-1during 2010 which increased to 235.83
± 11.4 kg km-1 day-1 in 2019 showing 207.5%
rise of C. carpio in a decade time. However,
the established population of C. carpio showed
predicted yield value of 170 ± 6 kg km-1 day-1in
2029. The calculated yield values for O. niloticus
was 57.51± 2.2 kg km-1 day-1 during 2010 which
increased to 151.13 ± 4.6 kg km-1 day-1 in 2019. The
biomass of C. gariepinus was 2.41 ± 033 kg km-1
day-1 in 2011, which increased to 39.82 ± 2.4 kg km-1
day-1 in 2019. The predicted yield was observed as
176 ±16.33 kg km-1 day-1 for Common Carp and
55.43 ± 6.4 kg km-1 day-1 for Tilapia in 2019 which
indicated that there may be 117.87% and 116.9%
yield rise in a decade’s time for Common Carp and
Tilapia, respectively, while 139.2% yield rise may
happen for invasive African Catfish for the same
period. The concrete and forecast values were
calculated considering 95% lower and upper level
of confidence, which was significant (p<0.05) and
the annual regression was found p<0.464, p<0.419
and p<0.499 for common carp, tilapia and African
catfish respectively. The confidence limit of 95%
for the forecasted variance in distribution had little
correlation with observed distribution. The median
variance was low but it was positive for the annual
Figure 3. Shifting seasonal pattern of rainfall at mid-stretch of the Ganga river during 1989 to 2019 (Source: IMD).
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27 23
regression of 0.02, 0.36 and 0.42 in C. carpio,
O. niloticus and C. gariepinus respectively for
concrete value. However, it was higher which were
0.06, 0.65 and 0.69 in C. carpio. O. niloticus and
C. gariepinus respectively for forecasted values
showing that the general variance for the next
10 year of forecast will predict a faster increase.
Obtained value for variance of R2 t) was 0.361
for C.carpio, 0.326 for O. nolitcius and 0.418 for
C. gareipinus. The observed MAW based forecast
of non-native tilapia, common carp and African
catfish catch for the period of 2020 to 2029 at 95%
confidence limit indicated a stable production in
the Ganga river and there was a positive pattern of
invasion meltdown.
Discussion
Invasive alien species have gained wider
recognition by scientists and policymakers in the
past decades due to their severe ecological and
economic impacts worldwide (Early et al., 2016;
Turbelin et al., 2017). Several freshwater fish
species have been translocated as a result of human
mediation and moved outside their native ranges by
an array of vectors such as deliberate introductions,
river corridors, and releases from aquaculture and
aquaria and even illegally introduced to arrive in
new environments (Singh and Lakra, 2011). An
increased trend of fish invasions has been recorded
over the years in inland waters of India. Climate
change is expected to alter seasonal patterns over
time with dramatic changes in precipitation and
temperature patterns. All of these factors combine
to place added stress on both native species.
However, invasive species in general are much
better equipped to handle these new stressors.
Seasonal change in temperature has a profound
effect on reproduction in fish. Temperature changes
cue reproductive development particularly in
monsoon spawning species. This in turn impacts
population replenishment and connectivity patterns
of local and invasive fishes. Warmer temperatures
modifies community structure and dynamics that
in turn facilitate invasions (Robert et al., 2017;
Manjarres-Hernandez et al., 2021; Arnaud et al.,
2021). Invasion of non-native introduced fishes
even in changing environments and climate exert
their effects on new habitats consequently emerging
as a major threat for ecosystems around the globe,
partly with irreversible consequences for the local
biota (Panlasigui et al., 2018). Invasive species
might cause habitat modification, extinctions of
endemic species, affect human health, and thus
exert enormous economic costs (Singh et al., 2013;
Singh et al., 2014; Panlasigui et al., 2018). Fish
invasions have also been reported to be driven by
climate change where synergies between climate
change and increased pressures of fish invasions
invite new management challenges for freshwater
ecosystem (Kernan, 2015).
Figure 4. Fish yield of recurrent invasive fish species in mid-stretch of the Ganga river.
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27
24
India has been placed at the 10th position
among highest climate risk countries in Asia
based on extreme environment events (Global
Sustainable Development Report 2015). Climate
variables namely the temperature, precipitation,
and humidity may have significant long-term
implications affecting water quality and fisheries
(Jayaraman and Murari 2014). Climate change
has been reported to exacerbate the threats posed
to the Inland fisheries by environmental stressors
(Das et al., 2019). The present study presents recent
data regarding increased incidence of non-native
Figure 5. Invasion prediction of common carp and yield contribution in the Ganga river using spatio-temporal population dynamics
model.
Figure 6. Invasion prediction of tilapia and yield contribution in the Ganga River using spatio-temporal population dynamics model.
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27 25
invasive species in the Ganga river especially
in the time of climate change. Using algorithms
and predictive models, future predictions on
range expansion of invasive species have been
reported by several workers (Fletcher et al., 2016;
ArchMiller et al., 2018; Dominguez et al., 2020).
In this study, predictive future invasional changes
for the upcoming decade have been presented. The
MAW based predictive values when calculated has
shown persistent increase of the three abundantly
available invasive fish C. carpio, O.niloticus and
C. gariepinus in the Ganga river during the next
decade. It is interesting to mention here that both
tilapia and common carp have depicted a very
similar trend of establishment and have exhibited
substantial growth in the Ganga river even in
adversely changing environmental and climatic
conditions. While the increased trend of invasion
of African catfish was even faster in recent years.
The increasing patterns of invasive fish species in
the Ganga river has been representing occupational
patterns and changed distribution of fishery
resources (Singh et al., 2013). Such rise in invasive
species in the river has caused decline in the
local fish catches and even change in biodiversity
patterns (Singh et al., 2013; Kernan, 2015; Mondal
and Bhat, 2020; Raj et al., 2021).
The results of this study have shown positive
and synergistic effects of Tilapia, Common Carp
and African Catfish on their increased catches after
invasion which strongly supports the ‘Invasion
meltdown’ (Simberloff and Von Holle 1999; Braga
et al., 2018). The findings indicate the phenomenon
that non-native invasive O. niloticus and C. carpio
have facilitated the invasion of the third one
i.e., C. gariepinus with good propagation and
compounded their independent impacts on native
species, communities and the riverine ecosystem
(Singh et al., 2013; K,ernan, 2015; Mondal and
Bhat, 2020; Raj et al., 2021). The potential role of
positive interactions among co-invaders has been
found at the core of the invasion meltdown. The
interaction of non-native tilapia, common carp
and African catfish has resulted in an exacerbation
of each other’s effects. Thus, the resulting
effect of multiple non-native species meltdown
on ecosystems can be greater than the sum of
the individual effects. It is thus, there is every
possibility that all the three invasive fish will spread
in newer areas of the Ganga river basin especially
in the changing climate and environments due to
their high adaptability and better survival (Deng
et al., 2020). Predictive biomass of the invaded
tilapia, common carp and African catfish warrant
Figure 7. Invasion prediction of African catfish and yield contribution in the Ganga River using spatio-temporal population
dynamics model.
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27
26
fishery managers to develop regulatory framework
to contain them at the earliest. Whilst mechanical,
chemical, and biological controls are the most
widely used approaches for controlling invasive
species, they require skilled manpower, technology,
and expertise, and can be extremely costly and
labour intensive. Therefore, early detection and
rapid response (EDRR) is key to the management
of invasive species in (Singh et al., 2013; Reaser
et al., 2020). Since there is no management plan
in the country to fight out invasive species in the
riverine ecosystem, it is advocated that effective
long-term management should be developed to
address the impacts of invasive alien species (IAS)
that cannot be eradicated. Policies and strategies
should be developed and implemented for the long-
term management of IAS in the riverine ecosystem.
Conclusions
The predictive forecast of invasive C. carpio,
O.niloticus and C. gariepinus in this study provides
a means for an evidence-based prioritization
of species and habitats for the management of
existing and future invasions of the Ganga river.
Further, it has also ascertained that the presence
of one invasive fish species facilitate another
and compound negative impacts on the aquatic
ecosystem. We thus, strongly point out that the
negative effects of invasive species meltdown
may be strong, even where no impact of single
invasion was expected. Thus, cumulative impacts
of multiple invasions will result in the replacement
of native species and consequently their extinction.
Acknowledgements
Authors are thankful to the fishermen societies
involved in regular fishing activities and markets
for sharing different catch information from time
to time.
References
ArchMiller AA, Dorazio RM, St. Clair K., and Fieberg
J.R., 2018. Time series sightability modeling of animal
populations. PLoS ONE 13(1), e0190706. https://doi.
org/10.1371/journal. pone.0190706.
Arnaud, S., Montoya Jose M., and Miguel L. (2021). Warming
indirectly increases invasion success in food webs.
Proceedings of the Royal Society B: Biological Sciences
288 (1947) DOI: 10.1098/rspb.2020.2622
Auffhammer M., Ramanathan V., and Vincent J.R., 2012.
Climate change, the monsoon, and rice yield in India.
Climate Change 111, 411–424.
Braga, R.R., Gomez-Aparicio, L., Heger, T. , Vitule J.R.S., and
Jeschke J.M., 2018. Structuring evidence for invasional
meltdown: broad support but with biases and gaps. Biol
Invasions 20, 923–936. https://doi.org/10.1007/s10530-
017-1582-2
Bucol, A.A., Galon, F.D. and Alcala, A. C., 2017. Catch-
per-unit effort of exploited finfishes and crustaceans in
Ilog river Estuary, Negros Occidental, Philippines. Peer
Journal Preprint 5, e2957v1, https://doi.org/10.7287/peerj.
preprints.2957v1].
Das, B.K., Sarkar, U.K. and Roy K., 2019. Global Climate
Change and Inland Open Water Fisheries in India: Impact
and Adaptations. In: S. Sheraz Mahdi (Ed.), Climate
Change and Agriculture in India: Impact and Adaptation,
pp.79-95. Springer International Publishing AG Part of
Springer Nature 2019. DOI: 10.1007/978-3-319-90086-5_8
Deng, W., Lin, L., Huang, X., Liao, T.-Y., and Kang, B., 2020.
Climate Change and Species Invasion Drive Decadal
Variation in Fish Fauna in the Min River, China. Water,
12(6), 1558. doi:10.3390/w12061558
Dominguez A. V., Palmer S.C.F., Gillingham P.K., Travis J.M.J.
and Britton J. R., 2020. Integrating an individual-based
model with approximate Bayesian computation to predict
the invasion of a freshwater fish provides insights into
dispersal and range expansion dynamics. Biol Invasions 22,
1461–1480. https://doi.org/10.1007/s10530-020-02197-6
Draper, N.R. and Smith, H., 1998. Applied Regression Analysis,
3rd Edn.. Wiley, New York, USA.
Early, R., Bradley, B.A., Dukes, J.S., Lawler, J.J., Olden, J.D.,
Blumenthal, D.M., Gonzalez, P., Grosholz, E.D., Ibanez, I.,
Miller, L.P., Sorte, C.J.B., Tatem, A.J., 2016. Global threats
from invasive alien species in the twenty-first century and
national response capacities. Nat. Commun. 7, 12485.
Fletcher D. H., Gillingham P. K., Britton J. R., Blanchet S.,
and Gozlan R. E., 2016. Predicting global invasion risks: a
management tool to prevent future introductions. Scientific
Reports 6, 26316 DOI: 10.1038/srep26316
Galil B.S., Nehring S., Panov V. (2008) Waterways as Invasion
Highways – Impact of Climate Change and Globalization.
In: W. Nentwig (Ed.), Biological Invasions. Ecological
Studies (Analysis and Synthesis), vol 193. Springer, Berlin,
Heidelberg. https://doi.org/10.1007/978-3-540-36920-2_5
Global Sustainable Development Report, 2015. United Nations,
Prototype Global Sustainable Development Report (UN-
DESA/DSD, 2015), https://sustainabledevelopment.un.org/
globalsdreport/2015.
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
Singh et al. / Aquatic Ecosystem Health and Management 24 (2021) 18–27 27
Hanley, N. and Michaela R., 2019. The economic benefits of
invasive species management. People and Nature. 1, 124–
137DOI: 10.1002/pan3.31published by John Wiley & Sons
Ltd on behalf of British Ecological Society.
Harsch, M.A., Zhou, Y., LambersJ.H., and Kot, M., 2014.
Keeping pace with climate change: stage-structured
moving-habitat models. The American Naturalist, 184, 25–
37.
Jayaraman T. and Murari K., 2014. Climate Change and
Agriculture: Current and Future Trends, and Implications for
India. Review of Agrarian Studies, 4(1), 1-49, available at:
http://www.ras.org.in/climate_change_and_agriculture_83
Kernan M., 2015. Climate change and the impact of invasive
species on aquatic ecosystems, Aquatic Ecosystem Health
Management 18 (3), 321-333 To link to this article: http://
dx.doi.org/10.1080/14634988.2015.1027636
Laplanchea, C., Elgera, A., Santoula, F., Thiedeb, G.P., Budyc,
P., 2018. Modelling the fish community population
dynamics and forecasting the eradication success of an
exotic fish from an alpine stream. Biological Conservation
223, 34-26.
Leeseberg, C.A. and Keeley E.R., 2014. Prey size, prey
abundance, and temperature as correlates of growth in
stream populations of Cutthroat trout. Environmental
Biology of Fishes 97, 599–614.
Leprieur, F., Beauchard, O., Blanchet, S., Oberdorff, T., Brosse,
S., 2008. Fish invasions in the world’s river systems: When
natural processes are blurred by human activities. PLoS
Biology 6, 0404–0410.
Manjarres-Hernandez A., Guisande C., Emilio Garcia-R.,
Juergen H., Pelayo-Villamil P., Perez-Costas E., Gonzalez-
Vilas L., Gonzalez-Dacosta J., Santiago R.D., Granado-
Lorencio C., Lobo J.M., 2021. Predicting the effects
of climate change on future freshwater fish diversity at
global scale. Nature Conservation 43, 1-24. http://doi.org/
10.3897/natureconservation.43.58997
Mondal R, and Bhat A., 2020. Temporal and environmental
drivers of fish-community structure in tropical streams
from two contrasting regions in India. PLoS ONE 15(4):
e0227354. https://doi.org/10.1371/journal.pone.0227354
Okubo, F., Yamashita, T. and Ogata, H., 2017. A neural network
approach for students, performance prediction. pp. 1-7.
In: Proceedings of the Seventh International Learning
Analytics and Knowledge Conference. Souvenir. March,
2017, Vancouver, British Columbia, Canada, https://doi.
org/10.1145/3027385.3029479.
Panlasigui S., Davis, A.J.S., Mangiante M.J., and Darling J.A.,
2018. Assessing threats of non-native species to native
freshwater biodiversity: Conservation priorities for the
United States. Biological Conservation 224, 199-208.
Raj Smrithy, Biju Kumar A., Tharian J., Raghavan R., 2021.
Illegal and unmanaged aquaculture, unregulated fisheries
and extreme climatic events combine to trigger invasions in
a global biodiversity hotspot. Biological Invasions. https://
doi.org/10.1007/s10530-021-02525-4 (Published online:16
April, 2021).
Reaser, J.K., Burgiel, S.W., Kirkey J., Brantley, K. A., Veatch
S. D. and Burgos-Rodriguez J., 2020. The early detection
of and rapid response (EDRR) to invasive species: a
conceptual framework and federal capacities assessment.
Biol Invasions 22, 1–19 (2020). https://doi.org/10.1007/
s10530-019-02156-w
Rolls, R. J., Hayden, B., and Kahilainen K.K., 2017.
Conceptualising the interactive effects of climate change
and biological invasions on subarctic freshwater fish.
Ecology & Evolution 7(12), 4109-4128 First published:
April https://doi.org/10.1002/ece3.2982
Simberloff, D. and Von Holle, B., 1999. Positive
interactions of non-indigenous species: invasional
meltdown? Biological Invasions 1: 21–32. https://doi.
org/10.1023/A:1010086329619.
Singh, A. K., Kumar D., Srivastava S.C., Ansari A., Jena
J. K. and Sarkar U. K., 2013. Invasion and Impacts of
Alien Fish Species in the Ganga River, India. Aquatic
Ecosystem Health & Management, 16(4), 408–414. DOI
10.1080/14634988.2013.857974.
Singh, A.K. and Srivastava, S.C., 2020. Logistic growth and
density-dependent spatial and temporal invasion predictions
of non-native tilapia, oreochomis niloticus (linnaeus 1757)
in the Ganga river, India. Applied Biological Research
India 22(3): 194-202. DOI:105958-0974-4517-2020
Singh, A.K. and Lakara, W.S., 2011. Risk and benefit assessment
of alien fish species of the aquaculture and aquarium trade
into India. Reviews in Aquaculture 3, 3-18.
Singh, A.K., Srivastava S.C., Verma P., Ansari A., and Verma A.,
2014. Hazard assessment of metals in invasive fish species
of the Yamuna River, India in relation to bioaccumulation
factor and exposure concentration for human health
implications. Environmental Monitoring and Assessment
10.1007/s10661-014-3660-6.
Thorson, J. T., Jannot, J., and Kayleigh, S., 2017. Using spatio-
temporal models of population growth and movement
to monitor overlap between human impacts and fish
populations. Journal of Applied Ecology 54(2), 577-587.
https://doi.org/10.1111/1365-2664.12664
Turbelin, A.J., Malamud, B.D., Francis, R.A., 2017. Mapping
the global state of invasive alien species: patterns of
invasion and policy responses. Global Ecol. Biogeogr. 26,
78e92.
Downloaded from http://scholarlypublishingcollective.org/msup/aehm/article-pdf/24/3/18/1471705/18singh.pdf by guest on 07 January 2022
ResearchGate has not been able to resolve any citations for this publication.
Article
Full-text available
Focusing on extreme climatic events in India’s Western Ghats Biodiversity Hotspot, we demonstrate that unmanaged aquaculture and unregulated fisheries can often combine with ECE in exacerbating biological invasions through the unexpected introduction and escape of novel alien species. High magnitude flooding events in August 2018 and 2019 resulted in the escape of at least ten alien fish species that were recorded for the first time, from the natural waters of the Western Ghats. Illegal farming systems, aqua-tourism destinations and amusement parks, as well as reservoirs, facilitated the escape of alien species during the ECE. Despite expanding invasions, unmanaged stocking and aquaculture using alien species continue in the Western Ghats, necessitating urgent management and policy interventions.
Article
Full-text available
Climate warming and biological invasions are key drivers of biodiversity change. Their combined effects on ecological communities remain largely unexplored. We investigated the direct and indirect influences of temperature on invasion success, and their synergistic effects on community structure and dynamics. Using size-structured food web models, we found that higher temperatures increased invasion success. The direct physiological effects of temperature on invasions were minimal in comparison with indirect effects mediated by changes on food web structure and stability. Warmer communities with less connectivity, shortened food chains and reduced temporal variability were more susceptible to invasions. The directionality and magnitude of invasions effects on food webs varied across temperature regimes. When invaded, warmer communities became smaller, more connected and with more predator species than their colder counterparts. They were also less stable and their species more abundant. Considering food web structure is crucial to predict invasion success and its impacts along temperature gradients.
Article
Full-text available
The aim of the present study was to predict future changes in biodiversity attributes (richness, rarity, heterogeneity, evenness, functional diversity and taxonomic diversity) of freshwater fish species in river basins around the world, under different climate scenarios. To do this, we use a new methodological approach implemented within the ModestR software (NOO3D) which allows estimating simple species distribution predictions for future climatic scenarios. Data from 16,825 freshwater fish species were used, representing a total of 1,464,232 occurrence records. WorldClim 1.4 variables representing average climate variables for the 1960–1990 period, together with elevation measurements, were used as predictors in these distribution models, as well as in the selection of the most important variables that account for species distribution changes in two scenarios (Representative Concentration Pathways 4.5 and 6.0). The predictions produced suggest the extinction of almost half of current freshwater fish species in the coming decades, with a pronounced decline in tropical regions and a greater extinction likelihood for species with smaller body size and/or limited geographical ranges.
Preprint
Full-text available
This paper reports the catch-per-unit effort (CPUE) of the finfish and crustacean fishery in Ilog River Estuary in Negros Occidental. We monitored catch data of fishing gears, mainly trawl (small type), beach seine and mud crab pot from April, May, September, October, December 2013 and January 2014.We estimated at least 37.82 metric tonnes of annual fishery yield (fishes and crustaceans combined) for the entire Malabong estuarine area. Two gears (liftnet and fish corrals) were used by the local fishers since the 1980s. Based on the baseline annual yield of 21 tonnes, the annual yield for these gears (at present ~7.5 tonnes) combined has declined by 13.5 tonnes (~65%) since the early 1980s (~30 years). This decline might be due to habitat degradation (including conversion of original mangrove forests into fish ponds and nipa plantations), over-exploitation, and organic pollution (resulting to recurring fish kill events) in the area.
Article
Full-text available
The changes in fishery yield owing to the exponential and logistic growth of non-native tilapia Oreochomi niloticus, was studied and its concrete and predictive invasion worked out so as to find out future level of invasion and yield from the Ganga river, India. The results showed that the abundance of O. niloticus ranged from 3.07 to 15.05% during 2009 to 2018 which increased continually at eight studied locations. At the same time, the average biomass yield day-1 also increased significantly (p < 0.05) in the same period. The calculated mean abundance by weight (MAW) showed that the average biomass was 51.95 kg day-1 km-1 during 2009 which increased to 151 ± 3 kg day-1 km-1 in 2018 showing 292% rise within a decade. The biomass-dependent tilapia population revealed significant (p < 0.05) increase in exponential and logistic growth over the years even in the degraded water quality having higher BOD and COD. The predicted increase in the mean abundance by weight-based biomass showed significant change and the annual-regression was p < 0.419 considering the incremental exponential and logistic growth. The predictive forecast of invasive tilapia catches for the period of 2018 to 2028 at 95% confidence limit suggests stable production from the Ganga river inviting attention of scientists and managers towards its management.
Article
Full-text available
Globalization necessitates that we address the negative externalities of international trade and transport, including biological invasion. The US government defines invasive species to mean, “with regard to a particular ecosystem, a non-native organism whose introduction causes, or is likely to cause, economic or environmental harm, or harm to human, animal, or plant health.” Here we address the role of early detection of and rapid response to invasive species (EDRR) in minimizing the impact of invasive species on US interests. We provide a review of EDRR’s usage as a federal policy and planning term, introduce a new conceptual framework for EDRR, and assess US federal capacities for enacting well-coordinated EDRR. Developing a national EDRR program is a worthwhile goal; our assessment nonetheless indicates that the federal government and its partners need to overcome substantial conceptual, institutional, and operational challenges that include establishing clear and consistent terminology use, strategically identifying and communicating agency functions, improving interagency budgeting, facilitating the application of emerging technologies and other resources to support EDRR, and making information relevant to EDRR preparedness and implementation more readily accessible. This paper is the first in a special issue of Biological Invasions that includes 12 complementary papers intended to inform the development and implementation of a national EDRR program.
Article
Full-text available
Freshwater fishes are threatened by increasing environmental changes and human disturbances. The Min River, the largest river in Southeastern China, contains unique fish fauna for the Oriental realm. Due to environmental changes brought by forty years of economic growth, fish numbers have dramatically declined. The average taxonomic distinctness in the 1970s was significantly higher than that in 2015, while no significant differences were found in the variation in taxonomic distinctness between the two periods. Due to the river network and habitat diversity, fish fauna composition showed significant spatial differences but lower variation than the decadal variation. Precipitation was determined to be the most influential factor in determining the spatial pattern of fish fauna, followed by temperature. Species introduced for aquaculture have invaded the endemic fish community after escape and should be reconsidered in the trade-offs between economic development and ecological protection.
Article
Full-text available
Environmental and anthropogenic factors are known to drive fish community structure in aquatic systems across the world. This study investigates fish assemblages in lower order streams across contrasting landscapes in central and eastern India. We documented the species diversity of these monsoon driven lower order streams in the two regions. We also investigated the potential common environmental drivers of richness and diversity and effect of season in these tropical streams. The study was based on seasonal data on abundance of fishes and environmental parameters collected between 2015–2017 from streams in states of Madhya Pradesh and West Bengal. Species diversity were compared across regions and seasons, based on their richness (SR) as well as diversity (Shannon index H'). Drivers of overall richness and diversity were analyzed using multiple linear regression methods, based on best subset selection. Analysis of data revealed high diversity in these streams in both regions. Cyprinidae, Bagridae and Channidae were the most dominant families in both regions. Despite the geographical and local ecological differences across the regions, common environmental parameters were found to influence richness and diversity across the two regions, indicating these as being key drivers of fish community structure. Water flow was a common factor driving both richness and diversity across both regions. Our study revealed a lack of seasonal effect in structuring fish communities in tropical streams. With stream and river ecosystems facing increasing threats due to habitat alterations and water quality degradation in countries such as India, a clear understanding of regional and local drivers of community structure of aquatic fauna is crucial. These results on the role of common environmental factors across ecoregions provides baseline information for understanding their ecological roles and developing management plans for important river basins and fish conservation in future.
Article
Full-text available
Short-distance dispersal enables introduced alien species to colonise and invade local habitats following their initial introduction, but is often poorly understood for many freshwater taxa. Knowledge gaps in range expansion of alien species can be overcome using predictive approaches such as individual based models (IBMs), especially if predictions can be improved through fitting to empirical data, but this can be challenging for models having multiple parameters. We therefore estimated the parameters of a model implemented in the RangeShifter IBM platform by approximate Bayesian computation (ABC) in order to predict the further invasion of a lowland river (Great Ouse, England) by a small-bodied invasive fish (bitterling Rhodeus sericeus). Prior estimates for parameters were obtained from the literature and expert opinion. Model fitting was conducted using a time-series (1983 to 2018) of sampling data at fixed locations and revealed that for 5 of 11 model parameters, the posterior distributions differed markedly from prior assumptions. In particular, sub-adult maximum emigration probability was substantially higher in the posteriors than priors. Simulations of bitterling range expansion predicted that following detection in 1984, their early expansion involved a relatively high population growth rate that stabilised after 5 years. The pattern of bitterling patch occupancy was sigmoidal, with 20% of the catchment occupied after 20 years, increasing to 80% after 30 years. Predictions were then for 95% occupancy after 69 years. The development of this IBM thus successfully simulated the range expansion dynamics of this small-bodied invasive fish, with ABC improving the simulation precision. This combined methodology also highlighted that sub-adult dispersal was more likely to contribute to the rapid colonisation rate than expert opinion suggested. These results emphasise the importance of time-series data for refining IBM parameters generally and increasing our understanding of dispersal behaviour and range expansion dynamics specifically.
Article
Full-text available
Invasive species are known to cause significant negative impacts to ecosystems and to people. In this paper, we outline the nature of these economic impacts, and then present a range of approaches for estimating the economic costs of invasive species (including impacts on biodiversity), and thus the benefits of management programmes. The importance of thinking clearly about the most appropriate context for valuation is stressed. We provide examples of the application of non‐market valuation approaches to invasive species management, and show how such methods can be used to measure public preferences over how control is undertaken. We discuss some important problems in applying economic valuation methods in this context. A plain language summary is available for this article.