Airborne lidar for woodland habitat quality monitoring: exploring the significance of lidar data characteristics when modelling organism-habitat relationships

Structure is a fundamental physical element of habitat, particularly in woodlands, and hence there has been considerable recent uptake of airborne lidar data in forest ecology studies. This paper investigates the significance of lidar data characteristics when modelling organism-habitat relationships, taking a single species case study in a mature woodland ecosystem. We re-investigate work on great tit (Parus major) habitat, focussing on bird breeding data from 1997 and 2001 (years with contrasting weather conditions and a demonstrated relationship between breeding success and forest structure). We use a time series of three lidar data acquisitions across a 12-year period (2000–2012). The lidar data characteristics assessed include time-lag with field data (up to 15 years), spatial sampling density (average post spacing in the range of 1 pulse per 0.14 m2–17.77 m2), approach to processing (raster or point cloud), and the complexity of derived structure metrics (with a total of 33 metrics assessed, each generated separately using all returns and only first returns). Ordinary least squares regression analysis was employed to investigate relationships between great tit mean nestling body mass, calculated per brood, and the various canopy structure measures from all lidar datasets. For the 2001 bird breeding data, the relationship between mean nestling body mass and mean canopy height for a sample area around each nest was robust to the extent that it could be detected strongly and with a high level of statistical significance, with relatively little impact of lidar data characteristics. In 1997, all relationships between lidar structure metrics and mean nestling body mass were weaker than in 2001 and more sensitive to lidar data characteristics, and in almost all cases they were opposite in trend. However, whilst the optimum habitat structure differed between the two study years, the lidar-derived metrics that best characterised this structure were consistent: canopy height percentiles and mean overstorey canopy height (calculated using all returns or only first returns) and the standard deviation of canopy height (calculated using all returns). Overall, our results suggest that for relatively stable woodland habitats, ecologists should not feel prohibited in using lidar data to explore or monitor organism–habitat relationships because of perceived data quality issues, as long as the questions investigated, the scale of analysis, and the interpretation of findings are appropriate for the data available

The declining occurrence of moose (Alces alces) at the southernmost edge of its range raise conservation concerns

The border region between Austria, the Czech Republic, and Germany harbors the most south-western occurrence of moose in continental Europe. The population originated in Poland, where moose survived, immigrated from former Soviet Union or were reintroduced after the Second World War expanded west and southwards. In recent years, the distribution of the nonetheless small Central European population seems to have declined, necessitating an evaluation of its current status. In this study, existing datasets of moose observations from 1958 to 2019 collected in the three countries were combined to create a database totaling 771 records (observations and deaths). The database was then used to analyze the following: (a) changes in moose distribution, (b) the most important mortality factors, and (c) the availability of suitable habitat as determined using a maximum entropy approach. The results showed a progressive increase in the number of moose observations after 1958, with peaks in the 1990s and around 2010, followed by a relatively steep drop after 2013. Mortality within the moose population was mostly due to human interactions, including 13 deadly wildlife-vehicle collisions, particularly on minor roads, and four animals that were either legally culled or poached. Our habitat model suggested that higher altitudes (ca. 700–1,000 m a.s.l.), especially those offering wetlands, broad- leaved forests and natural grasslands, are the preferred habitats of moose whereas steep slopes and areas of human activity are avoided. The habitat model also revealed the availability of large core areas of suitable habitat beyond the current distribution, suggesting that habitat was not the limiting factor explaining the moose distribution in the study area. Our findings call for immediate transboundary conservation measures to sustain the moose population, such as those aimed at preventing wildlife-vehicle collisions and illegal killings. Infrastructure planning and development activities must take into account the habitat requirements of moose.publishedVersio

Decline of the boreal willow grouse (Lagopus lagopus) has been accelerated by more frequent snow-free springs

Climate change has influenced a range of species across the globe. Yet, to state a noted decline in the abundance of a given species as a consequence of a specific environmental change, for instance, spatially explicit long-term data are a prerequisite. This study assessed the extent to which prolonged snow-free periods in autumn and spring have contributed to the decline of the willow grouse, the only forest grouse changing into a white winter plumage. Time-series data of willow grouse numbers from summer surveys across the study area were integrated with local data on weather (snow cover), mammalian predator abundance and hunting intensity. Modelling was conducted with a hierarchical Bayesian Poisson model, acknowledging year-, area- and location-specific variability. The results show that while willow grouse numbers had decreased continuously across the study landscapes, the decrease was accelerated at the sites where, and during the years when the preceding April was the most snow-free. This indicates a mismatch between the change into a white winter plumage and the presence of snow, turning the bird into an ill-camouflaged prey. The results thus also confirm past hypotheses where local declines of the species have been attributed to prolonged snow-free periods. Across our study area, autumns and springs have become more snow-free, and the trend has been predicted to continue. Thus, in addition to conservation actions, the future of a species such as the willow grouse is also dependent on its ability to adapt to the changed environmental conditions.202

Behavioral modifications by a large-northern herbivore to mitigate warming conditions

Background: Temperatures in arctic-boreal regions are increasing rapidly and pose significant challenges to moose (Alces alces), a heat-sensitive large-bodied mammal. Moose act as ecosystem engineers, by regulating forest carbon and structure, below ground nitrogen cycling processes, and predator-prey dynamics. Previous studies showed that during hotter periods, moose displayed stronger selection for wetland habitats, taller and denser forest canopies, and minimized exposure to solar radiation. However, previous studies regarding moose behavioral thermoregulation occurred in Europe or southern moose range in North America. Understanding whether ambient temperature elicits a behavioral response in high-northern latitude moose populations in North America may be increasingly important as these arctic-boreal systems have been warming at a rate two to three times the global mean. Methods: We assessed how Alaska moose habitat selection changed as a function of ambient temperature using a step-selection function approach to identify habitat features important for behavioral thermoregulation in summer (June–August). We used Global Positioning System telemetry locations from four populations of Alaska moose (n = 169) from 2008 to 2016. We assessed model fit using the quasi-likelihood under independence criterion and conduction a leave-one-out cross validation. Results: Both male and female moose in all populations increasingly, and nonlinearly, selected for denser canopy cover as ambient temperature increased during summer, where initial increases in the conditional probability of selection were initially sharper then leveled out as canopy density increased above ~ 50%. However, the magnitude of selection response varied by population and sex. In two of the three populations containing both sexes, females demonstrated a stronger selection response for denser canopy at higher temperatures than males. We also observed a stronger selection response in the most southerly and northerly populations compared to populations in the west and central Alaska. Conclusions: The impacts of climate change in arctic-boreal regions increase landscape heterogeneity through processes such as increased wildfire intensity and annual area burned, which may significantly alter the thermal environment available to an animal. Understanding habitat selection related to behavioral thermoregulation is a first step toward identifying areas capable of providing thermal relief for moose and other species impacted by climate change in arctic-boreal regions.publishedVersio

Drivers of ungulate behavior in the context of human-wildlife conflicts : The effects of food, fear and temperature on ungulate landscape use and impacts

Ungulates inhabiting managed landscapes generate important ecosystem services. However, their landscape use may cause negative impacts on human land uses. Expanding ungulate populations in Europe lead to increased human-wildlife conflict, but is also perceived as positive by stakeholders that favor high ungulate numbers. Hence, there is a need for management strategies that consider both the positive and the negative impacts of ungulates, for example by managing their behavior in addition to numbers. In this thesis, I investigated how three key functional landscapes; the foodscape, the landscape of fear and the thermal landscape influenced ungulate landscape use and impacts. I also explored the role humans have in shaping these landscapes. I did this by using an array of methods: field inventories, landscape experiments, social data collection and GPS-data. I found that food, fear and temperature strongly influenced how ungulates used the landscape. In addition, I showed how humans shape the three functional landscapes, for example by changing the foodscape through crop planting or forestry activities, leading to consequences on ungulate impact on human land use. Finally, I found that crop damage was reduced by experimentally inducing fear. Hence, my thesis suggests that it is possible to steer ungulate behavior by managing these functional landscapes. My thesis highlights the importance of including behavioral drivers when managing ungulates and regarding the effects of humans on these drivers. I conclude that these drivers often interact with each other influencing ungulate behavior, and that there is a need for more holistic approaches looking across land use and landowner borders in order to efficiently manage ungulate communities in managed landscape

Movement activity and space use

Fear of predation is a major selective pressure for prey species and, although important for survival, can have adverse effects on the well-being of the animals. Human disturbance has been shown to elicit the same behavioural and physiological responses, in particular in hunted species. Using GPS-data from a heavily hunted moose population in northern Sweden, I investigated differences in habitat selection and activity patterns between two valleys contrasting in human disturbance, during both peak and low tourism seasons. The effects of temperature, precipitation, and wind speed were also considered. I found moose to alter their habitat utilisation to use more protective habitats during the peak tourism seasons in the valley with high human disturbance, whereas open habitats were used more in the valley with low disturbance. I found no evidence for activity patterns being impacted by tourism, and the weather variables were of low importance. My study suggests that moose habitat selection is indeed affected by increased human disturbance. There is a need for studies on the long-term impacts on fitness on this displacement of moose into protective habitats. In addition, bodily measurements are required to assess physiological stress responses that are not visible in the behaviour of the animals. These findings, in combination with future studies, can help managers with the planning of further recreational sprawl into moose habitats

Behavioral modifications by a large-northern herbivore to mitigate warming conditions

Background Temperatures in arctic-boreal regions are increasing rapidly and pose significant challenges to moose (Alces alces), a heat-sensitive large-bodied mammal. Moose act as ecosystem engineers, by regulating forest carbon and structure, below ground nitrogen cycling processes, and predator-prey dynamics. Previous studies showed that during hotter periods, moose displayed stronger selection for wetland habitats, taller and denser forest canopies, and minimized exposure to solar radiation. However, previous studies regarding moose behavioral thermoregulation occurred in Europe or southern moose range in North America. Understanding whether ambient temperature elicits a behavioral response in high-northern latitude moose populations in North America may be increasingly important as these arctic-boreal systems have been warming at a rate two to three times the global mean. Methods We assessed how Alaska moose habitat selection changed as a function of ambient temperature using a step-selection function approach to identify habitat features important for behavioral thermoregulation in summer (June–August). We used Global Positioning System telemetry locations from four populations of Alaska moose (n = 169) from 2008 to 2016. We assessed model fit using the quasi-likelihood under independence criterion and conduction a leave-one-out cross validation. Results Both male and female moose in all populations increasingly, and nonlinearly, selected for denser canopy cover as ambient temperature increased during summer, where initial increases in the conditional probability of selection were initially sharper then leveled out as canopy density increased above ~ 50%. However, the magnitude of selection response varied by population and sex. In two of the three populations containing both sexes, females demonstrated a stronger selection response for denser canopy at higher temperatures than males. We also observed a stronger selection response in the most southerly and northerly populations compared to populations in the west and central Alaska. Conclusions The impacts of climate change in arctic-boreal regions increase landscape heterogeneity through processes such as increased wildfire intensity and annual area burned, which may significantly alter the thermal environment available to an animal. Understanding habitat selection related to behavioral thermoregulation is a first step toward identifying areas capable of providing thermal relief for moose and other species impacted by climate change in arctic-boreal regions

Missä hirvet elävät? : Hirvien elinpiirit ja habitaattivalinta Pohjanmaalla

Hirvi on Suomen merkittävin riistaeläin, jonka takia sitä on myös tutkittu paljon. Hirvien vaatimukset habitaattien suhteen vaihtelevat mm. vuodenaikojen mukaan. Tehokkaan hirvikannan hoidon varmistamiseksi on habitaattivalintaa tutkittava eri puolilla Suomea, sillä ympäristöolosuhteet vaihtelevat alueittain suuresti. Tässä tutkimuksessa selvitettiin, kuinka laajoja hirvien kesä- ja talvielinpiirit ovat sekä minkälaisia habitaatteja hirvet suosivat Pohjanmaan alueella kesäisin ja talvisin. Habitaattivalintaa tarkasteltiin kahdella eri tasolla: elinpiirin valintaa maisematasolla sekä habitaattivalintaa elinpiirin sisällä. Aineistona käytettiin 33:n GPS-pannoitetun hirven paikannustietoja vuosien 2009-2011 väliltä. Paikannustiedot projisoitiin monilähde-VMI:n päälle, joka oli uudelleenluokiteltu 15 luokkaan. Tulosten perusteella urosten elinpiirit ovat keskimäärin huomattavasti laajempia kuin naaraiden. Kausien välillä tilastollisesti merkitseviä eroja ei löytynyt. Kesäisin hirvet suosivat elinpiiritasolla sekapuustoisia ja muita taimikoita sekä -nuoria metsiä. Talvisin taas suosittiin mäntyvaltaisia taimikoita ja nuoria metsiä sekä välteltiin peltoja ja muita alueita. Sukupuolittain tarkasteltuna tilastollisesti merkitseviä eroja ei löytynyt. Elinpiirien sisäisellä tasolla hirvet suosivat kesäisin lähes kaikkia sekapuustoisia ja muita metsäluokkia sekä nuoria turvepohjaisia mäntymetsiä ja varttuneita mäntymetsiä. Peltoja, vesistöjä ja muita alueita sen sijaan välteltiin. Talvisin hirvet siirtyivät keskimäärin nuorempiin metsäluokkiin suosien lähes kaikkia taimikoita ja nuoria metsiä. Talvisin kaikkia varttuneita metsiä ja peltoja välteltiin. Naaraat suosivat kesäisin uroksia selkeämmin lähes kaikkia sekapuustoisia ja muita metsäluokkia sekä nuoria turvepohjaisia mäntymetsiä. Molemmat sukupuolet välttelivät peltoja, vesialueita ja muita alueita. Talvisin molemmat sukupuolet suosivat lähes kaikkia taimikoita ja nuoria metsiä. Peltoalueita välteltiin hyvin selkeästi. Useamman habitaattivalinnan valinnan tason käyttäminen on välttämätöntä, jotta saataisiin selville, mitä habitaattiluokkia hirvet todella suosivat tai välttelevät ja kuinka voimakkaasti

Taimiuutiset 2/2016

4 Tutkimusta tulevaisuuden istutusketjuista 6 Kuusi valtaa alaa 10 Voiko laserkeilauksella löytää hirvituhoalueita? 13 Kuusen solukkolisäyksen tutkimus jatkuu Lukessa 17 Kuusen ja männyn taimien kasvua ja rakennetta voi ohjata erilaisilla valon spektreillä 21 Taimien talveentumiskehitys tulevaisuuden ilmasto-olosuhteissa: Erilaisia reaktioita eri puulajeilla ja alkuperillä 23 Peittoaineiden vaikutus kasvualaustan vesipitoisuuteen ja kuusen taimien kasvuun 26 Hallakastelun käyttö pakkasvaurioiden estämiseen 29 Siemenlevintäinen Diplodia pinea -sien havaittu ensi kertaa Suomessa 31 Erinomainen kirja kasvihuoneviljelystä 31 Laatua ja monimuotoisuutta metsänuudistamiseen 32 Puupelto-city sarjakuva Listaa artikkelit201