Mammals
Railway disturbance impacts differ among mammal species. Besides the higher
intensity of light and noise (it can achieve 120 dB), small mammals can be found
near the railways if there is no grazing disturbance (Qian et al. 2009), or if the
unnatural nature of rail bed and tracks is not an obstacle to their movements (van
der Grift 1999). In fact, the richness of small mammal species was high at the
railway verge in the Atlantic forest in southern Brazil (Cerboncini 2012), probably
because the noise from the trains can force predators out of the area, which can
favor small mammals’ appearance (Cerboncini 2012). Similarly, railways may have
a positive role in maintaining the common bat populations in highly humanized
landscapes, such as intensive agriculture. In this case, railway verges seem to be
used as shelters for bat species despite the traffic noise; only Myotis sp. foraging
behaviour was negatively affected by railway verges (Vandevelde et al. 2014).
Although the response of large mammals to the effects of railway disturbance
varies among species, they seem to ignore railway disturbances. However, there is
evidence that the presence of railways had a subtle effect on some species’ behaviour.
For example, railways had little effect on the distance or direction of fox dispersal
movements (Trewhella and Harris 1990); however, the railway disturbance may have
influenced the fox movements within their territories (Trewhella and Harris 1990).
Similarly, the Canadian Pacific Railway in Banff National Park seems to redirect wolf
movements (individuals follow the railway), particularly when the snow is deep
(Paquet and Callaghan 1996), while it seems to define the boundary of bears’ home
ranges (Kaczensky et al. 2003). As detected for other species groups, changes in the
railway verges can attract large mammals. In Banff National Park, railway verges
attracted black and grizzly bears (Ursus americanus and U. arctos, respectively) due
to the berry-producing areas within the verges (Gibeau and Herrero 1998). Grain
spills along the Canadian Pacific rail line also attract bears (Gibeau and Herrero
1998), while food spills seem to increase the abundance of mice, which may attract
their predators, such as the coyote (Wells 1996).
By contrast, railways seem to be avoided by two large ungulates: Mongolian
gazelles (Procopra gutturosa) and Tibetan antelopes (Pantholops hodgsoni). No
observations of Mongolian gazelle crossings during dispersal were detected, and most
of the individuals were found 300 m from the railway (Ito et al. 2005). Likewise,
there were no Tibetan antelope crossings (Xia et al. 2007) because these antelopes
hesitated to cross the railway, most likely because of the slope of the rail bed.
Mitigation Measures to Reduce Railway Disturbances
There are several measures to reduce the main negative effects of railway disturbances (Schulte-Werning et al. 2008; Maeda et al. 2012; Nielsen et al. 2015).
Although some of these measures are known to effectively reduce the major
88
P.S. Lucas et al.
Railway disturbance impacts differ among mammal species. Besides the higher
intensity of light and noise (it can achieve 120 dB), small mammals can be found
near the railways if there is no grazing disturbance (Qian et al. 2009), or if the
unnatural nature of rail bed and tracks is not an obstacle to their movements (van
der Grift 1999). In fact, the richness of small mammal species was high at the
railway verge in the Atlantic forest in southern Brazil (Cerboncini 2012), probably
because the noise from the trains can force predators out of the area, which can
favor small mammals’ appearance (Cerboncini 2012). Similarly, railways may have
a positive role in maintaining the common bat populations in highly humanized
landscapes, such as intensive agriculture. In this case, railway verges seem to be
used as shelters for bat species despite the traffic noise; only Myotis sp. foraging
behaviour was negatively affected by railway verges (Vandevelde et al. 2014).
Although the response of large mammals to the effects of railway disturbance
varies among species, they seem to ignore railway disturbances. However, there is
evidence that the presence of railways had a subtle effect on some species’ behaviour.
For example, railways had little effect on the distance or direction of fox dispersal
movements (Trewhella and Harris 1990); however, the railway disturbance may have
influenced the fox movements within their territories (Trewhella and Harris 1990).
Similarly, the Canadian Pacific Railway in Banff National Park seems to redirect wolf
movements (individuals follow the railway), particularly when the snow is deep
(Paquet and Callaghan 1996), while it seems to define the boundary of bears’ home
ranges (Kaczensky et al. 2003). As detected for other species groups, changes in the
railway verges can attract large mammals. In Banff National Park, railway verges
attracted black and grizzly bears (Ursus americanus and U. arctos, respectively) due
to the berry-producing areas within the verges (Gibeau and Herrero 1998). Grain
spills along the Canadian Pacific rail line also attract bears (Gibeau and Herrero
1998), while food spills seem to increase the abundance of mice, which may attract
their predators, such as the coyote (Wells 1996).
By contrast, railways seem to be avoided by two large ungulates: Mongolian
gazelles (Procopra gutturosa) and Tibetan antelopes (Pantholops hodgsoni). No
observations of Mongolian gazelle crossings during dispersal were detected, and most
of the individuals were found 300 m from the railway (Ito et al. 2005). Likewise,
there were no Tibetan antelope crossings (Xia et al. 2007) because these antelopes
hesitated to cross the railway, most likely because of the slope of the rail bed.
Mitigation Measures to Reduce Railway Disturbances
There are several measures to reduce the main negative effects of railway disturbances (Schulte-Werning et al. 2008; Maeda et al. 2012; Nielsen et al. 2015).
Although some of these measures are known to effectively reduce the major
88
P.S. Lucas et al.