ESM Schippers et al. 2015. Rapid diversity loss of competing animal species in wellconnected landscapes.
S2 Table. Species survival in the landscape of aditional simulations
ESM Table S2. Surviving number of species in the metapopulation after 1000 years in different
simulations and competitive settings.
competitive
scale (fragmentation)
setting
1.0
1.2 1.6 2.4 4.0
7.2 13.6 26.4 52.0 103.2 205.6
Reference simulations
independent
21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0
coexisting
3.7
4.8 6.5 8.7 11.5 15.0 17.1 17.9 17.6 17.6 17.7
neutral
1.0
1.1 1.7 3.8 7.9 14.1 15.9 15.7 16.4 16.1 16.0
excluding
1.1
1.9 3.0 7.3 13.4 14.8 15.9 15.3 14.8 15.1 15.2
hierarchical
1.0
1.0 1.3 1.4 3.0
7.7 11.6 13.6 14.1 13.4 14.0
Clustered initialization from 1 reproductive unit per patch to 10 reproductive units per patch
independent
21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0
coexisting
3.6
5.2 6.6 9.3 11.5 14.3 16.7 17.7 17.5 18.0 17.7
neutral
1.0
1.2 1.8 4.0 9.2 15.5 17.8 17.8 18.3 18.5 17.1
excluding
1.1
1.9 3.8 9.3 15.3 17.6 18.0 17.7 18.3 18.2 18.1
hierarchical
1.0
1.0 1.1 2.1 4.0 10.9 16.6 17.2 17.9 17.1 17.6
Carrying capacity decreases from 20 to 15 breeding pairs
independent
21.0 21.0 21.0 21.0 21.0 21.0 21.0 20.6 20.3 20.5 20.4
coexisting
2.5
2.7 4.1 5.4 6.6
8.7
8.2
8.2 8.6 8.1
7.5
neutral
1.0
1.3 1.9 4.1 6.9
7.3
6.7
6.4 6.0 6.0
6.4
excluding
1.0
1.8 2.9 4.6 7.7
6.5
5.2
5.9 4.8 4.7
5.0
hierarchical
1.0
1.0 1.3 2.0 4.5
6.7
6.3
5.8 5.8 5.6
5.2
Carrying capacity increases from 20 to 40 breeding pairs
independent
21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0 21.0
coexisting
8.5
12.0 14.7 18.0 20.2 20.8 21.0 20.9 21.0 21.0 21.0
neutral
1.0
1.1 1.8 4.6 9.4 16.5 19.7 20.5 20.5 20.6 20.7
excluding
1.2
1.8 3.6 13.2 19.5 20.3 20.5 20.6 20.6 20.7 20.7
hierarchical
1.0
1.0 1.1 1.2 1.6
2.3
6.2 12.3 14.4 15.7 15.1
Patch size range increases from 0.25-0.75 to 0.05-0.95 km 2
independent
21.0 21.0 21.0 21.0 21.0 21.0 21.0
coexisting
4.6
6.9 8.9 11.8 13.8 17.4 18.7
neutral
1.0
1.0 1.7 3.7 8.2 13.8 17.0
excluding
1.2
1.7 3.6 9.3 14.8 15.9 16.4
hierarchical
1.0
1.0 1.2 1.5 2.4
5.9 10.6
Reproduction at zero density decreases from 1.8 to 1.4 juvenile per female
independent
20.0 20.0 20.0 20.0 20.1 19.7 18.5
coexisting
2.2
3.1 3.8 5.2 6.7
6.2
5.4
neutral
1.0
1.2 1.9 3.9 5.8
5.1
3.9
excluding
1.1
1.4 2.5 4.4 5.5
4.2
3.0
hierarchical
1.0
1.1 1.5 2.5 5.2
4.8
4.1
Dispersal fraction at carrying capacity decreases from 0.6 to 0.3
independent
21.0 21.0 21.0 21.0 21.0 21.0 21.0
coexisting
5.7
8.3 10.7 14.2 16.4 18.6 19.4
neutral
1.6
3.3 6.6 13.4 16.8 18.1 18.5
excluding
4.3
9.1 14.2 16.0 17.3 17.8 17.1
hierarchical
1.1
1.4 2.3 4.5 9.4 13.2 15.4
Dispersal dependent on density of all species
independent
20.0 20.0 20.0 20.0 20.0 20.0 20.3
coexisting
3.6
3.1 2.8 2.8 5.4
8.8 11.5
neutral
1.0
1.0 1.1 2.2 5.4
9.5 10.9
excluding
1.0
1.1 1.9 2.9 7.0
9.7
8.8
hierarchical
1.0
1.0 1.2 2.5 5.5 10.3 10.7
Each patch has an independent environmental stochasticity
independent
21.0 21.0 21.0 21.0 21.0 21.0 21.0
coexisting
3.7
4.7 5.9 8.6 11.3 14.4 16.3
neutral
1.0
1.1 1.5 2.9 8.0 14.6 16.0
excluding
1.2
1.4 2.4 6.2 11.5 14.7 15.6
hierarchical
1.0
1.0 1.2 1.5 2.8
8.4 12.5
Each species gets a random competition index between a ij= 0.4-1.6
random
1.3
1.6 1.8 2.7 5.5 10.6 14.0
21.0
19.3
17.1
17.4
13.1
21.0
19.3
17.8
16.7
13.5
21.0
19.6
17.6
17.5
14.0
21.0
19.2
18.2
16.3
14.0
16.8 15.5 15.6
5.3 5.4 5.3
4.0 4.5 3.9
3.8 2.7 2.7
4.3 4.4 3.8
15.7
4.4
3.9
2.9
3.5
21.0
19.1
18.4
17.6
15.3
21.0
19.6
18.0
17.0
15.6
21.0
19.7
18.2
17.6
15.8
20.9 20.9 20.8
11.5 12.0 12.3
9.8 8.8 9.7
8.5 8.1 8.1
10.0 9.5 10.3
21.0
11.4
9.5
8.1
9.4
21.0
17.1
17.0
15.1
14.1
21.0
17.6
16.6
15.3
14.2
21.0
17.6
16.7
15.3
13.8
15.6 15.8 16.2
15.5
21.0
19.6
18.6
17.4
15.5
21.0
17.9
16.8
15.2
14.1
Explanation of S2 Table simulations
Here we describe briefly the changes made to the reference settings and the impact of these
changes on the species survival at various fragmentation levels after 1000 years.
Clustered initial species distribution,
We initialized the reference simulations with one breeding pair (one male, one female) of
each species in each patch meaning that all species are initially present in all patches. To test
how this initial setting might affect the outcome of the competition, we initialize the
simulations in a contrasting, more clustered way. Hence, we initialized a set of new
simulations with 20 breeding pairs of a single species in five patches. So, each patch starts
being occupied by a single species.
Results resemble the reference simulations to a large extent (ESM Table S2) only at high
isolation levels the diversity is a bit higher due to this different initialization (ESM Table S2).
Carrying capacity decreased
When we reduce the carrying capacity of an average patch from 20 breeding pairs to 15
reproductive units per patch we see that the general patterns roughly match that of the
reference simulations (ESM Table S2). However, the general diversity level is lower.
Carrying capacity increased
When we double the carrying capacity to 40 breeding pairs per patch. The increase of
carrying capacity results in higher diversity levels in all the simulations (ESM Table S2)
while the diversity is always increasing with isolation. Especially the diversity in the
coexisting case at low isolation increased from 3.7 to 8.5 species. However also here the
diversity levels are higher at higher fragmentation levels
Patch size range increased
In the reference simulations the patch size range is 0.25 - 0.75 km2 which corresponds with a
carrying capacity of 10-30 breeding pairs. Here, we increase this range to 0.05 - 0.95 km2
which corresponds to a carrying capacity of 2 - 38 breeding pairs. The increase of the patch
variability results in a small diversity increase in most competitive settings (ESM Table S2).
Reproduction at low density decreases
We decrease the maximum recruitment from 1.8 to 1.4 (juveniles per female). This decrease
in reproduction causes a strong decrease in the diversity in all the competitive settings.
Furthermore there is a marked diversity optimum at intermediate fragmentation levels in all
competitive settings (ESM Table S2). However also here the diversity levels are higher at
higher fragmentation levels
Dispersal fraction at carrying capacity decreases
Here we decrease the dispersal fraction at carrying capacity from 0.6 to 0.3 (year-1)
This decrease in the dispersal fraction causes an increase of the diversity in all of the
competitive settings. Especially the excluding competitive setting profit from the decrease in
dispersal (ESM Table S2). It seems that lowering the dispersal probability lowers the adverse
effects species have upon each other. Nevertheless diversity after 100 years was much higher
at higher fragmentation levels.
Dispersal based on multi-species density,
In the reference simulations the dispersal of individuals is governed by the density of that
species in the local patch. Here, we let the density of all species in the patch determine the
dispersal of all individuals, so also from other species. We do this because if species
experience competition from other species they are likely to respond to their presence. The
introduction of this new density dependent dispersal causes a strong decrease of the diversity
in all competitive settings (ESM Table S2).
Each patch has an independent environmental stochasticity,
In the reference simulations the environmental stochasticity of the recruitment and survival
was completely synchronized among species and patches. Here we test the effect of spatial
differences in environmental stochasticity for patches and species. No effect of this
uncorrelated environmental stochasticity on the results was found (ESM Table S2).
Each species gets a random competition index
In our reference simulations, excluding hierarchical competition, we assume equal
competition strength between highly similar species but in reality species in a community will
have all levels of competitive species interactions. Therefore, we performed a series of
simulations with randomly drawn competitive interaction aij between 0.4 and 1.6. Meaning
that every species has 20 different randomly drawn aij which define its competiveness to the
20 other species. For every simulation we completely redraw the competition matrix between
species. On average these new simulations match the reference simulations for neutral and
excluding competition (ESM Table S2).