The train trips with high speed recording were between the Madrid and Albacete
stations (321.7 km) of the Madrid-Levante line, which includes the section in which
all field experiments were developed. A total of 66 trip recordings were collected
over different seasons (14–20 per season). There were five additional trips during
which the technical equipment was set up and tested (data not included). In all, 59 h
and 55 min of recording (average trip, 55.3 min) along 14,700 km of accumulated
train motion (average trip, 226.2 km; range: 78.3–288.7 km) were analyzed.
These recordings yielded 1090 confirmed bird observations, including 39 collisions (3.6% of observations), yielding a mortality risk of 0.0026 killed birds per
km (1 hit per 406.1 km). Direct observation from the cockpit provided a new
perspective in the analysis of the reactions of birds facing an approaching
train. Train speed during bird collisions (mean ± standard deviation, 265.8 ±
39.2 km/h; range 175–305 km/h; N = 20) was similar to that during under-catenary
crossings (251.5 ± 58.9 km/h; range 0–305 km/h; N = 183). However, in all
cases, bird collisions occurred with trains travelling at high speeds. Collision rates
varied seasonally, consistent with prior observations (SEO/BirdLife 1997; Frías
1999; Carvalho and Mira 2011; Bishop and Brogan 2013; Loss et al. 2014). The
roadkill rate varied between 0.0018 and 0.0032 birds/km, with a noteworthy constant percentage of under-catenary crossings in front of the train resulting in collisions (*12.2 ± 0.01%). These data suggest that train speed determines mortality
risk independent of particular species’ characteristics, with the risk being a result of
the fact that birds are not adapted to avoiding objects approaching at such high
velocities (Martin 2011; DeVault et al. 2015; Lima et al. 2015). Previous studies
have pointed out that birds have difficulty avoiding vehicles travelling over 80–
90 km/h (Pallag 2000; DeVault et al. 2014, 2015). The lowest speeds of collision
recorded in our study were *180 km/h, similar to the findings of DeVault et al.
(2015), who suggested that such speeds exceed birds’ abilities to escape
successfully.
Given these data and the infeasibility of reducing train speeds, information
obtained from recordings with respect to birds’ infrastructure use and behavior
when facing a train, particularly in cases of collision, is of great interest. Of all
recorded birds, 29.4% flew below the catenary (i.e. through the risk area), a datum
similar to that registered in previous field studies (33.1, see above section). Cockpit
recordings enabled us to determine that 37.7% of the birds that crossed the risk area
were using some element of the infrastructure moments before their train
encounters. That is, they commenced flight (most likely) due to the approach of the
train, but crossed in front of it. Among the data obtained from the train, it is
remarkable that 40.1% of the detected birds were initially observed in the infrastructure, and 28% of them crossed below the catenary. In addition, 5 of 29 collisions recorded from the cockpit (17.2%) involved birds resting on or in the
infrastructure. Therefore, a high percentage of the birds that are finally exposed to
the risk of collision were using the railway as a place to rest or feed. Hence,
corrective measures, such as barriers designed to raise the flight of birds above the
catenary (LIFE+ Impacto 0 2016), should also deter birds from HSR structures in
order to reduce bird mortality risk in the HSR.
8 Cross-scale Changes in Bird Behavior Around …
129
stations (321.7 km) of the Madrid-Levante line, which includes the section in which
all field experiments were developed. A total of 66 trip recordings were collected
over different seasons (14–20 per season). There were five additional trips during
which the technical equipment was set up and tested (data not included). In all, 59 h
and 55 min of recording (average trip, 55.3 min) along 14,700 km of accumulated
train motion (average trip, 226.2 km; range: 78.3–288.7 km) were analyzed.
These recordings yielded 1090 confirmed bird observations, including 39 collisions (3.6% of observations), yielding a mortality risk of 0.0026 killed birds per
km (1 hit per 406.1 km). Direct observation from the cockpit provided a new
perspective in the analysis of the reactions of birds facing an approaching
train. Train speed during bird collisions (mean ± standard deviation, 265.8 ±
39.2 km/h; range 175–305 km/h; N = 20) was similar to that during under-catenary
crossings (251.5 ± 58.9 km/h; range 0–305 km/h; N = 183). However, in all
cases, bird collisions occurred with trains travelling at high speeds. Collision rates
varied seasonally, consistent with prior observations (SEO/BirdLife 1997; Frías
1999; Carvalho and Mira 2011; Bishop and Brogan 2013; Loss et al. 2014). The
roadkill rate varied between 0.0018 and 0.0032 birds/km, with a noteworthy constant percentage of under-catenary crossings in front of the train resulting in collisions (*12.2 ± 0.01%). These data suggest that train speed determines mortality
risk independent of particular species’ characteristics, with the risk being a result of
the fact that birds are not adapted to avoiding objects approaching at such high
velocities (Martin 2011; DeVault et al. 2015; Lima et al. 2015). Previous studies
have pointed out that birds have difficulty avoiding vehicles travelling over 80–
90 km/h (Pallag 2000; DeVault et al. 2014, 2015). The lowest speeds of collision
recorded in our study were *180 km/h, similar to the findings of DeVault et al.
(2015), who suggested that such speeds exceed birds’ abilities to escape
successfully.
Given these data and the infeasibility of reducing train speeds, information
obtained from recordings with respect to birds’ infrastructure use and behavior
when facing a train, particularly in cases of collision, is of great interest. Of all
recorded birds, 29.4% flew below the catenary (i.e. through the risk area), a datum
similar to that registered in previous field studies (33.1, see above section). Cockpit
recordings enabled us to determine that 37.7% of the birds that crossed the risk area
were using some element of the infrastructure moments before their train
encounters. That is, they commenced flight (most likely) due to the approach of the
train, but crossed in front of it. Among the data obtained from the train, it is
remarkable that 40.1% of the detected birds were initially observed in the infrastructure, and 28% of them crossed below the catenary. In addition, 5 of 29 collisions recorded from the cockpit (17.2%) involved birds resting on or in the
infrastructure. Therefore, a high percentage of the birds that are finally exposed to
the risk of collision were using the railway as a place to rest or feed. Hence,
corrective measures, such as barriers designed to raise the flight of birds above the
catenary (LIFE+ Impacto 0 2016), should also deter birds from HSR structures in
order to reduce bird mortality risk in the HSR.
8 Cross-scale Changes in Bird Behavior Around …
129