accidents (Pearson’s r = 0.82, P < 0.05) and the number of elephants killed
per year (r = 0.96, P < 0.0001). Between 1974 and 2002, when meter gauge
(MG) was in operation, 27 elephants died in 26 accidents, corresponding to
0.90 accidents/year ±1.11 (SD) and 0.93 ± 1.19 (SD) elephants/accident. In the
12 years (2004–2015) after conversion to broad gauge (BG), these figures jumped
to 62 fatalities in 35 accidents, corresponding to 2.92 accidents/year ±1.98
(SD) and 5.17 ± 5.89 (SD) elephants/accident. There were statistically significant
differences between the time periods before and after gauge conversion, for both the
annual number of accidents (Mann–Whitney U = 283.5, Z = −3.13, P < 0.001)
and the annual number of animals killed (Mann–Whitney U = 290.5, Z = −3.33,
P < 0.001).
We also analyzed data in more detail for accidents occurring from 2004 to 2015
(after gauge conversion). Females accounted for most of the animals killed in
train collisions, while adults (>15 years) constituted nearly 60% of all mortality
recorded (Table 10.2). Also noteworthy is the relatively high mortality of calves
(Table 10.2). Comparing these figures with available data on the age structure of
elephant populations in northern West Bengal (Sukumar et al. 2003), we found that
adult elephant males were killed far more frequently (31% or more than 2.5–fold)
than what would have been expected from their representation in the population
(13%; Table 10.2). A proportions test also showed that adult males (Z = 3.831,
P < 0.001), and calves (Z = 2.136, P = 0.037) were involved to a significantly
greater extent in train accidents (n = 62) than their representation in the population
(n = 650).
0
10
20
30
40
50
60
Number
No inc
ele killed
Fig. 10.1 Temporal variation between 1974 and 2015 in the number of train–elephant collision
accidents (No inc) and in the number of elephants killed (ele killed) per 5-year period, in the
Siliguri–Alipurduar railway, northern West Bengal, India
10 Railways and Wildlife: A Case Study …
163
per year (r = 0.96, P < 0.0001). Between 1974 and 2002, when meter gauge
(MG) was in operation, 27 elephants died in 26 accidents, corresponding to
0.90 accidents/year ±1.11 (SD) and 0.93 ± 1.19 (SD) elephants/accident. In the
12 years (2004–2015) after conversion to broad gauge (BG), these figures jumped
to 62 fatalities in 35 accidents, corresponding to 2.92 accidents/year ±1.98
(SD) and 5.17 ± 5.89 (SD) elephants/accident. There were statistically significant
differences between the time periods before and after gauge conversion, for both the
annual number of accidents (Mann–Whitney U = 283.5, Z = −3.13, P < 0.001)
and the annual number of animals killed (Mann–Whitney U = 290.5, Z = −3.33,
P < 0.001).
We also analyzed data in more detail for accidents occurring from 2004 to 2015
(after gauge conversion). Females accounted for most of the animals killed in
train collisions, while adults (>15 years) constituted nearly 60% of all mortality
recorded (Table 10.2). Also noteworthy is the relatively high mortality of calves
(Table 10.2). Comparing these figures with available data on the age structure of
elephant populations in northern West Bengal (Sukumar et al. 2003), we found that
adult elephant males were killed far more frequently (31% or more than 2.5–fold)
than what would have been expected from their representation in the population
(13%; Table 10.2). A proportions test also showed that adult males (Z = 3.831,
P < 0.001), and calves (Z = 2.136, P = 0.037) were involved to a significantly
greater extent in train accidents (n = 62) than their representation in the population
(n = 650).
0
10
20
30
40
50
60
Number
No inc
ele killed
Fig. 10.1 Temporal variation between 1974 and 2015 in the number of train–elephant collision
accidents (No inc) and in the number of elephants killed (ele killed) per 5-year period, in the
Siliguri–Alipurduar railway, northern West Bengal, India
10 Railways and Wildlife: A Case Study …
163