Thesis Defence Seminar on Red Squirrels

As part of her PhD thesis defense, Wild49 member Jessica Haines will be presenting a one-hour public seminar at 1pm on January 12, 2017, in room CCIS 1-243 at the University of Alberta. Her talk title and abstract are below.


Resources and Reproductive Trade-offs Affect Fitness, Life History Traits, and Sexual Selection in Red Squirrels
Animals face trade-offs throughout life between competing functions, such as between self-maintenance, reproduction, and survival. Resource allocation between these competing functions leads to different patterns of life history traits, changes in investment in reproductive effort, and different patterns of reproductive success. Reproductive investment is also influenced by the environment, for example by resource availability or mating opportunities. In this thesis, I test for evidence of reproductive and life history trade-offs, as well as for whether individual- and population-level resource availability affect reproduction and life history traits. I first tested whether there was evidence of age-related changes in reproductive success in male red squirrels, and in particular whether there was evidence of senescent decline in older ages. I also considered whether there was a trade-off between early-life reproduction and late-life senescence in male red squirrels. Next, I tested whether encountering a resource pulse affected life history traits. I also explored whether life history trade-offs and the fitness consequences of life history traits were affected by encountering a resource pulse called a mast year. Finally, I tested whether individual-level food availability was related with breeding season timing and reproductive success in male and female red squirrels.

 

Seminar: Ferruginous Hawk (Buteo regalis) responses to human disturbance during the breeding season

Here is a young female Ferruginous Hawk sporting her new bands.On the left leg (her right leg) is the field-readable colour band and the silver band with serial number is on the right leg. Photo: Janet Ng.

Ferruginous Hawk on a nest, photo by Janet Ng

Today (14 December 2015) Cameron Nordell will give a public seminar as part of his MSc thesis defense. Come hear about his research at 1pm in the University of Alberta Biological Sciences Building, room CW 313.

 

Talk Summary:

The expansion of the human footprint across the world is increasing the number of interactions between humans and wildlife. Many studies have quantified wildlife behavioural responses to humans and this is an active area of research with practical implications for species conservation. However, changes to individual animals behaviour may be influenced by the properties of the disturbance stimulus itself, the effect of the environment in which the interaction occurs, and the individual’s past experience, but these potentially important effects have rarely been evaluated. Additionally it is unclear how individuals behave in the hours following the departure of human disturbance. In southern Alberta and Saskatchewan, I quantified the flight initiations from the nest by Ferruginous Hawks (Buteo regalis) in response to approaching investigators and used digital video systems to quantify their behaviour following investigator departure.

In Chapter 2 I studied the flight initiation distance from the nest (FID) by adult Ferruginous Hawks. FID was related to the actions of the investigator, the anthropogenic landscape around the nest and the number of previous visits to Ferruginous Hawk nests by investigators. Approaches by humans on foot illicit longer FIDs than those in a vehicle. Approaches driving on private access roads that were infrequently used by vehicles were related to increased FID. My data show that shorter FIDs are related greater number of vehicles that pass near a nest, demonstrating a relationship between human disturbances around the nest and FID. Finally, Ferruginous Hawk FIDs increased as the number of previous investigator approaches to that nest increased. Chapter 2 highlights the dynamic and complex nature of the decision to initiate flight from the nest and provides new insight as to why FID varies between and within species.

Having explored factors influencing the Ferruginous Hawk’s decision to change behaviour in response to human disturbance in Chapter 2, Chapter 3 focuses on the behavioural consequence through time when disturbed by humans. Here, I used digital video footage of Ferruginous Hawk nests to document nesting behaviour of adult males and females up to 12 hrs following an investigator disturbance, and test non-exclusive hypotheses that may explain differences in behaviour relative to undisturbed control periods. On average, across the 12 hr sample period, female Ferruginous Hawk spent significantly less time on the nest following investigator disturbance relative to controls, but individual variation was high. Delivery of prey items to the nest not significant different between disturbance and control sample periods. Disturbed female time on nest, initially lower than control periods, returned to normal over the course of our 12 hr sample period. The duration of reduced time on nest by the female varied with age and number of nestlings, such that female time on nest returned to normal sooner following a disturbance for young nestlings, and with larger broods. Thus, I found support for both the harm-to-offspring and parental investment hypotheses. This is among the first studies to identify that disturbed animals demonstrate behavioural differences from normal for up to 12 hrs following disturbance.

The ability to adapt flight initiation behaviour to human approaches and the consistent delivery of prey when disturbed suggests that, Ferruginous Hawks nesting in the highly anthropogenic regions of southern Alberta and Saskatchewan demonstrate the behavioural plasticity necessary to coexist with some human disturbance to the nest site. However, I also found instances of Ferruginous Hawk flight initiation at large distances, and that some individuals reduced nest attendance for lengthy durations following a human disturbance. Understanding how these extreme behaviours affect reproductive success of Ferruginous Hawks is likely essential to understanding human impacts on the Ferruginous Hawk population in Canada. My research was intended to contribute to the ongoing conservation effort for this species, and I discuss potential implications for management in Chapter 4. My research provides novel insight into disturbed behaviour and can inform management policies in the future as human development in the grasslands ecoregions expands and increases the number of interactions between humans and Ferruginous Hawks.

Public Seminar: The use of citizen science to identify the factors affecting bird-window collisions at residential houses

On Tuesday, December 8, Justine Kummer will be presenting a public seminar for her MSc defence. Come hear about her research in the University of Alberta Biological Sciences Building room CW 313 at 1pm.

Bird Feeders 2

Talk Summary

Every year a large number of birds die when they collide with windows. The actual number however is difficult to ascertain. Previous attempts to estimate bird-window collision rates in Canada relied heavily on a citizen science study that used memory-based surveys which may have potential biases. Building upon this study and their recommendations for future research the Birds and Windows citizen science project was designed to have homeowners actively search for collision evidence at their houses and apartments for an extended period. The first objective of the Birds and Windows project was to see how a more standardized approach to citizen science data collection influenced bird-window collision estimates and to see if the same patterns observed by memory-based surveys were observed using different data collection methods. Comparing the results from the Birds and Windows standardized searches and memory-based surveys revealed differences in absolute values of collisions but similar relative rankings between residence types. This suggests that memory-based surveys may be a useful tool for understanding the relative importance of different risk factors causing bird-window collisions.

The second objective from the Birds and Windows project was to gain a better understanding of the factors affecting collisions at residential houses. It currently remains poorly understood which types of buildings and windows are most problematic. Understanding whether neighbourhood type, yard conditions, house attributes, or window types have the largest effect on collision rates is crucial for identifying which mitigation options might be most effective. Factors at the yard level had the best model fit for predicting bird-window collisions at residential houses. Conservation efforts should target variables at this level and those factors that attract birds to an individual yard. As few homeowners are likely to take an approach that reduces the number of birds in their yards, focus should instead be given to bird-friendly urban design and developing the most effective window deterrents.

Finally, the effects of bird feeder presence and placement on bird-window collisions at residential homes was determined through a manipulative experiment. During the study there were 1.84 times more collisions when the bird feeder was present. However, there were no collisions at half of the study windows. High variance was observed in the number of collisions at different houses, indicating that effects of bird feeders are context dependent. Changing the occurrence, timing, and placement of feeders can alter collision rates but is only one of many factors that influence whether a residential house is likely to have a bird-window collision or not.

In conclusion, I provide recommendations for conducting future survey-based citizen science projects and outline the next steps for bird-window collision research in working towards stopping avian mortality from collisions with windows. I have thoroughly outlined a number of factors affecting bird-window collisions and the focus of future research should now shift towards reducing the problem. The Birds and Windows project saw a number of successes as a citizen science project and citizen science remains the best method for collecting large scale data in real-world scenarios and should continue to be used in similar experiments.

Bird Feeders 3

Seminar: Projecting boreal bird responses to climate change: considering uncertainty, refugia, time lags, and barriers

Diana Stralberg will be presenting her thesis defense seminar on Tuesday, November 3 at 1pm in the University of Alberta Biological Sciences Building room CW313. Check out her abstract below.

Photo by Craig Machtans, Environment Canada.

Photo by Craig Machtans, Environment Canada.

Abstract: Often referred to as North America’s bird nursery, the boreal forest biome provides a resource-rich environment for breeding birds, supporting high species diversity and bird numbers. These birds are likely to shift their distributions northward in response to rapid climate change over the next century, resulting in population- and community-level changes. Using a new continental-scale avian dataset, I have developed models to project climate-induced changes in the distribution and relative abundance of 80 boreal-breeding passerine species. For such projections to be useful, however, the magnitude of change must be understood relative to the magnitude of uncertainty in model predictions. In my first chapter, I found that the mean signal-to-noise ratio across species increased over time to 2.87 by the end of the 21st century, with the signal greater than the noise for 88% of species. I also found that, among sources of uncertainty evaluated, the choice of climate model was most important for 66% of species, sampling error for 29% of species, and variable selection for 5% of species. In addition, the range of projected changes and uncertainty characteristics across species differed markedly, suggesting the need for a variety of approaches to climate change adaptation.

Species and ecosystems may be unable to keep pace with rapid climate change projected for the 21st century, however. In my second chapter, I evaluated an underexplored dimension of the mismatch between climate and biota: limitations to forest growth and succession affecting habitat suitability. I found that end-of-century projected changes in songbird distribution were reduced by up to 169% when vegetation lags were considered, indicating that limits to forest growth and succession may result in dramatic reductions in suitable habitat for many species over the next century. I used these results to identify conservative and efficient boreal conservation priorities anchored around climatic macrorefugia that are robust to century-long climate change and complement the current protected areas network.

Vegetation change may also be delayed in the absence of disturbance catalysts. In the western boreal region, a combined increase in wildfires and human activities may aid these transitions, also resulting in a younger forest. In my third chapter, I developed a hybrid modelling approach based on topo-edaphically constrained projections of climate-driven vegetation change potential, coupled with weather- and fuel-based simulations of future wildfires, and projections of large-scale industrial development activities, to better understand factors influencing decadal-scale upland vegetation change. I simulated scenarios of change in forest composition and structure over the next century, conservatively concluding that at least one-third of Alberta’s upland mixedwood and conifer forest is likely to be replaced by deciduous woodland and grassland by 2090, with a disproportionate loss of both young and old forest classes. During this timeframe, the rate of increase in fire probability diminished, suggesting a negative feedback process by which a warmer climate and more extensive near-term fires leads to an increase in deciduous forest that in turn, due to its relatively low flammability, leads to a long-term reduction in area burned.

Finally, boreal species’ projected range shifts could be impeded by the northwestern cordillera, which separates boreal Alaska from the rest of the North American boreal region, and appears to have historically prevented many species from expanding into climatically suitable habitat after the last glacial maximum (LGM). Using paleoclimate simulations for the past 20,000 years, I analyzed the relative importance of migratory and life-history characteristics vs. climatic factors on the distributions of North American boreal-breeding species. I then used this information to predict which species are most likely to shift their distributions from Canada into the Alaskan boreal region in the future. The high relative importance of climatic suitability within the northwestern cordilleran region suggests a capacity for several species to disperse into Alaska once climatic connectivity is achieved in the future, which is supported by recently recorded signs of breeding activity.

Seminar – Fear, Forage, and Snowfall: Deer Habitat Selection and Population Dynamics in Alaska’s Temperate Rainforest

Sophie Gilbert holding one of the subjects of her research: a Sitka black-tailed deer fawn.

Sophie Gilbert holding one of the subjects of her research: a Sitka black-tailed deer fawn.

This Friday (9 Oct, 2015) at noon, Wild49 lab member Sophie Gilbert will present a public seminar in the Biological Sciences building room M149. Check out the summary of her talk:

The coastal temperate rainforest is one of the rarest ecosystems in the world, and a major portion of the global total is found in Southeast Alaska. In this ecosystem, Sitka black-tailed deer are the dominant large herbivore, influencing large carnivores that prey on deer such as wolves and bears, as well as plant species and communities through browsing. In addition, deer play an important economic and cultural role for humans in Southeast Alaska, making up the large majority of terrestrial subsistence protein harvested each year as well as providing the backbone of a thriving tourism industry built around sport hunting. Given the importance of deer in this system, there remain a surprisingly large number of gaps in our knowledge of deer ecology in Southeast Alaska. These knowledge gaps are potentially troubling in light of ongoing industrial timber-harvest across the region, which greatly alters habitat characteristics and value to wildlife. This talk covers the results of a 4-year research project to quantify 1) patterns of reproduction and fawn survival, 2) population dynamics in response to environmental variability, and the underlying drivers of spatial selection during 3) reproduction and 4) winter. In addition, the talk will include the results of a recent wolf-deer-habitat modeling effort aimed at understanding outcomes of future land-use, climate, and trapping scenarios on wolf abundance.

Twin fawns with radio collars, photo by Sophie Gilbert.

Twin fawns with radio collars, photo by Sophie Gilbert.

Non-invasive sampling provides insights into carnivore ecology via mark-recapture, occupancy, and genetic connectivity for elusive top predators such as jaguars and tigers

A fully grown adult male tiger photographed by a camera Trap, photo by Marcella Kelly.

A fully grown adult male tiger photographed by a camera trap set up by Marcella Kelly’s lab.

Marcella Kelly, an Associate Professor at the Virginia Tech Dept. of Fish & Wildlife Conservation, will be presenting a seminar at the University of Alberta this week. Her talk will be in the Biological Sciences Building room M149 at 2pm on Friday, September 11.

Jaguar photographed by a trail camera set up by Marcella Kelly's lab.

Abstract: Remote camera trapping and molecular scatology have enabled researchers to gain valuable information on previously intractable, elusive top predators. For jaguars in Belize, camera trapping techniques have enabled us to examine the co-existence of multiple predators simultaneously to determine whether jaguars function as an umbrella species or whether meso-predators are suppressed by high numbers of the top predator. Additionally, using scat samples collected with the aid of detector dogs, combined with molecular scatology, we find evidence of a generally well-mixed jaguar population in Belize, yet a faint hint of population sub-structure exists, pointing to the importance of maintaining targeted wildlife corridors. For tigers in Nepal, camera trapping in the forested, hilly habitat known as the Churia, previously considered unsuitable, has revealed a healthy (albeit lower density) tiger population and a potentially thriving leopard population. Unlike Belize however, landscape genetics from molecular scatology in Nepal has revealed a highly structured tiger population with low levels of gene flow among tiger sub-populations. Habitat restoration or targeted translocations may be necessary to maintain genetic connectivity across the landscape.