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Local government planning agencies play an important role in conserving biodiversity in human-altered landscapes. Such agencies frequently have a limited knowledge of wildlife biology and few resources to carry out research, and therefore require simple, practical guidelines for biodiversity conservation. We propose a landscape design framework for biodiversity conservation that is sequential, prescriptive, and supported by current landscape ecological science. Unlike existing guidelines, our framework can be implemented in any given landscape using only land cover data and it explicitly considers constraints on land use planning. The steps of our framework, in the order in which they should be implemented are: (1) select land cover data and decide which land cover classes constitute unaltered or altered land covers; (2) list the constraints on land use planning (e.g., economic, social) that exist for the landscape; (3) maximize the total amount and diversity of unaltered land cover, especially near water; (4) minimize human disturbance within altered land cover, especially near water; and (5) aggregate altered land covers associated with high-intensity land uses, especially away from water. We illustrate the utility of our approach by applying it to a hypothetical landscape and comparing the outcome to those from the application of traditional ecological guidelines to inform land use planning.

In habitats disturbed by anthropogenic noise, acoustically communicating species may develop behavioral responses that help them transmit information and overcome signal masking. We studied four anuran species breeding in wetlands, ponds, and ditches near a highway in eastern Ontario, Canada, to test whether they called more often when traffic noise intensity was lower, and stopped calling when the noise intensity increased (i.e., gap calling behavior). We made call recordings between April and July 2011, and compared the traffic noise intensity (sound pressure level) between times when the anurans were calling and times when they were not calling. We found that the two species with the highest call peak frequency (American toad, gray treefrog) called randomly with regard to traffic noise intensity. In contrast, the two species with the lowest call peak frequency (green frog, bullfrog) called more often when traffic noise intensity was low. The behavioral response in the two latter species likely represents a short-term strategy that enhances their signal-to-noise ratio thereby increasing the chance of effective communication. Our results support predictions derived from the acoustic adaptation hypothesis: low-frequency signals are more prone to be masked by anthropogenic noise and therefore require behavioral adjustments (in this study gap-calling behavior) to ameliorate this effect.

Roads are linked to population declines in amphibians, primarily due to road mortality. Culvert-type ecopassages, along with fencing to direct animals to the passage, have been used to mitigate these impacts. However, the effectiveness of the ecopassage itself, independent of the associated mitigation fencing, is largely untested. In regions with heavy snowfall, long-term maintenance of amphibian-proof fencing is extremely costly. Therefore, it is important to know whether ecopassages alone (without fencing) mitigate amphibian mortality. We used a Before-After-Control-Impact design to experimentally test the hypothesis that pre-existing drainage culverts of the type typically used to mitigate road effects on herptiles mitigate anuran road mortality. Grates were installed at both ends of 6 culverts to exclude anurans from the culverts. At an additional 4 sites fencing was installed on either side of culverts on both sides of the road, to keep anurans off the road. Ten control culverts were left u...

We previously found that males of two anuran species – Hyla versicolor and Rana clamitans – alter their mating calls in response to traffic noise. To test whether these alterations compensate for an effect of traffic noise on mate attraction, we (1) recorded a male calling at a quiet site; (2) played traffic noise at the same male and recorded its altered call; (3) used these recordings to attract females to a trap at sites either with or without broadcast traffic noise. The calls produced without traffic noise attracted fewer females when they were played at sites with traffic noise than when they were played at sites without noise. However, the calls of the same individuals produced with traffic noise attracted as many females at sites with noise as at sites without noise, and they attracted as many females as did the call of the same male made without noise and played at sites without noise (the ‘natural’ situation). Therefore, for these species, traffic noise does not affect mate attraction; males change their calls to compensate for a potential effect of traffic noise on mate attraction. A third species – Bufo americanus – does not alter its call in response to traffic noise, and its call made in the absence or presence of traffic noise was equally able to attract females in the absence or presence of traffic noise, indicating that traffic noise does not negatively affect mate attraction. Therefore, it appears that traffic noise does not negatively affect mate attraction in these three species of anurans. We suggest that, if our results apply to anurans in general, the previously documented negative effects of roads on anuran populations are likely caused mainly by road mortality. If this is true, road mitigation for anurans should focus mainly on reducing this mortality.

Summary 1. The effects of roads on wildlife populations are widespread and well documented. Many studies have shown that bird abundance, occurrence and species richness are reduced near roads, with the largest reductions where traffic levels are high. Negative correlations have been reported between bird richness ⁄ abundance and traffic noise but the possible causes of road effects are inter-correlated. It is important to disentangle the different effects so that appropriate mitigation measures can be implemented. 2. We tested the hypothesis that traffic noise is a key negative effect by testing three predictions: (i) bird richness ⁄ abundance should reach a maximum at the same distance from roads that traffic noise reaches a minimum; (ii) the effect of traffic noise on bird richness ⁄ abundance should be stronger than the effect of distance from the road on bird richness ⁄ abundance; and (iii) sites with more traffic noise at a given distance from the road should show lower bird richness ⁄ abundance than sites with less traffic noise at the same distance. 3. We collected breeding bird occurrence and traffic noise data along twenty 600-m transects perpendicular to roads at 10 high-traffic road sites. 4. Traffic noise decreased and bird species richness increased with increasing distance from the roads. However, none of the predictions derived from the traffic noise hypothesis was supported. 5. Synthesis and applications. Our results suggest that traffic noise is not the main cause of the negative relationship between bird species richness ⁄ abundance and proximity to roads. Instead, traffic mortality may be the main mechanism causing this relationship. We suggest that mitigation of road impacts on birds should focus mainly on reducing mortality rather than reducing traffic noise. In particular, engineering road surfaces, tyres and vehicle engines to reduce noise would not mitigate road effects; instead, structures to keep birds away from roads or force them to fly above the traffic would be more effective.

Many species use acoustic signals to attract mates, and such signals can be degraded by anthropogenic noise. Anuran abundance has been shown to be negatively correlated with road traffic which could be due in part to the interruption of mate attraction by traffic noise. However, this impact could be small if anurans can alter their vocalization characteristics to avoid masking of their calls by traffic noise. We predicted that: (i) anuran vocalization characteristics (dominant frequency, mean amplitude and call rate) should be different in areas with different traffic noise levels; (ii) increases in traffic noise can cause immediate changes in amphibian vocalization characteristics; (iii) these altered vocalizations are similar to those at high traffic sites. To test the first prediction we compared vocalizations of four species of anuran at breeding sites in locations with low traffic noise vs. sites with high traffic noise. For the second prediction we broadcast traffic noise at low traffic (quiet) sites, and compared the anuran vocalizations before vs. during the broadcast traffic noise. For the third prediction we compared vocalizations at high traffic sites to those produced at low traffic sites while broadcasting traffic noise. Three species of anurans found at locations with low traffic noise produced vocalizations with different characteristics than individuals of the same species found in locations with high traffic noise. Broadcast traffic noise immediately altered amphibian vocalization characteristics such that they became similar to those of the same species found in locations with high traffic noise. We conclude that plasticity in the vocalizations of anurans allows for the maintenance of acoustic communication in the presence of traffic noise.

Temperature is often an important determinant of species presence and activity patterns, but observations of temperature at fine resolution and broad extents—scales relevant to individual organisms—are rare. We analyzed how biotic and abiotic variables influence ground surface temperature (GST) using high-resolution thermal data for a 1900-ha area of forest and field near Wasaga Beach, Ontario, Canada. Temperature was recorded at 2-h intervals from May to October, 2004 and 2005, from data loggers approximately 300 m apart. At the same sites, we recorded overstory and understory vegetation, elevation, and distances to the nearest road and urban infrastructure. Correspondence Analysis (CA) indicated that thermal conditions varied most strongly seasonally and diurnally. Canonical Correspondence Analysis (CCA) pinpointed which biotic and abiotic variables were related to surface temperature. Canopy cover and leaf litter cover were positively related to cool sites during both cool and warm periods. Si...

While conducting a study of home range and habitat use of the eastern hognose snake (Heterodon platirhinos) in Southern Ontario, we observed both mating and nesting behaviors for this species. Here we describe the active excavation of oviposition sites by H. platirhinos; mating behavior, including multiple copulations of a single female with five males; and philopatry to specific nest sites by multiple individuals in successive years. As our study site is close to the northern limit of this species' range, nest sites may need to be carefully selected to provide a thermal regime warm enough to incubate the eggs. Mean nest temperatures in the field ranged from 23.4 to 26.1 C, while incubation periods ranged from 49 to 63 d.

Strategies to reduce wildlife road mortality have become a significant component of many conservation efforts. However, their success depends on knowledge of the temporal and spatial patterns of mortality. We studied these patterns along the 1000 Islands Parkway in Ontario, Canada, a 37 km road that runs adjacent to the St. Lawrence River and bisects the Algonquin-to-Adirondacks international conservation corridor. Characteristics of all vertebrate road kill were recorded during 209 bicycle surveys conducted from 2008 to 2011. We estimate that over 16,700 vertebrates are killed on the road from April to October each year; most are amphibians, but high numbers of birds, mammals, and reptiles were also found, including six reptiles considered at-risk in Canada. Regression tree analysis was used to assess the importance of seasonality, weather, and traffic on road kill magnitude. All taxa except mammals exhibited distinct temporal peaks corresponding to phases in annual life cycles. Variations in weather and traffic were only important outside these peak times. Getis–Ord analysis was used to identify spatial clusters of mortality. Hot spots were found in all years for all taxa, but locations varied annually. A significant spatial association was found between multiyear hot spots and wetlands. The results underscore the notion that multi-species conservation efforts must account for differences in the seasonality of road mortality among species and that multiple years of data are necessary to identify locations where the greatest conservation good can be achieved. This information can be used to inform mitigation strategies with implications for conservation at regional scales.

Oviposition and fecundity in the grain miteAcarus siro were studied at 5–30°C and 62.5–90% RH. At and above 20°C, 80% RH, mating and oviposition occurred soon after emergence, but at lower temperatures and humidities egg laying was progressively delayed from one to several days. Females needed to mate repeatedly in order to achieve maximum egg production, optimum conditions for which were 15°C, 90% RH, where total output per female averaged 435 with a maximum of 858. Oviposition rates were highest at higher temperatures, the mean daily rate at 20 and 25°C, 90% RH, rising to maximum levels of 28/29 eggs per female per day on day six.

The grain or flour mite, Acarus siro L. (formerly called Tyroglyphus farinae L.) is a serious and widespread pest of stored foodstuffs, particularly grain and grain products. Recently, Griffiths (1964) has shown that the flour mite represents a complex of three species, Acarus siro L., sensu Griffiths 1964, which appeared to be the dominant species found in stored-product habitats, A. farris (Ouds. 1905) and A. immobilis Griffiths 1964, which seemed to be field species sometimes transported to storage premises. For some years, a comprehensive study of the rates of survival, development and reproduction of A. siro has been in progress at this laboratory. The present paper describes the results of experiments carried out to determine the physical limits for survival and complete development of this species. Since these experiments were begun, other authors have published studies covering the same ground but in less detail. The present results seem worth publishing because of their greater precision and also because it is useful to record the similarities and differences between mites from different regions or on different food materials. Also, Griffiths' work indicates that some of the published information on A. siro may be based on misidentifications of A. farris and A. immobilis. Although the effects of temperature and humidity are interdependent I have found it convenient, for purposes of presentation, to deal with them separately as far as possible.