scholarly journals Prescribed burning in a mediterranean-climate region mitigates the disturbance by bushfire to a critical food resource for an endangered bird, the Carnaby’s cockatoo

Fire Ecology ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Valerie S. Densmore ◽  
Emma S. Clingan

Abstract Background Prescribed burning is used to reduce fire hazard in highly flammable vegetation types, including Banksia L.f. woodland that occurs on the Swan Coastal Plain (SCP), Western Australia, Australia. The 2016 census recorded well over 1.9 million people living on the SCP, which also encompasses Perth, the fourth largest city in Australia. Banksia woodland is prone to frequent ignitions that can cause extensive bushfires that consume canopy-stored banksia seeds, a critical food resource for an endangered bird, the Carnaby’s cockatoo (Calyptorynchus latirostris, Carnaby 1948). The time needed for banksias to reach maturity and maximum seed production is several years longer than the typical interval between prescribed burns. We compared prescribed burns to bushfires and unburned sites at three locations in banksia woodland to determine whether low-intensity prescribed burns affect the number of adult banksias and their seed production. Study sites were matched to the same vegetation complex, fire regime, and time-since-fire to isolate fire intensity as a variable. Results Headfire rates of spread and differenced normalized burn ratios indicated that prescribed burning was generally of a much lower intensity than bushfire. The percentage survival of adult banksias and their production of cones and follicles (seeds) did not decrease during the first three years following a prescribed burn. However, survival and seed production were significantly diminished followed high-intensity bushfire. Thus, carrying capacity for Carnaby’s cockatoo was unchanged by prescribed burning but decreased markedly following bushfire in banksia woodland. Conclusions These results suggest that prescribed burning is markedly different from bushfire when considering appropriate fire intervals to conserve canopy habitats in fire-resilient vegetation communities. Therefore, low-intensity prescribed burning represents a viable management tool to reduce the frequency and extent of bushfire impacts on banksia woodland and Carnaby’s cockatoo.

2003 ◽  
Vol 12 (2) ◽  
pp. 117 ◽  
Author(s):  
Paulo M. Fernandes ◽  
Hermínio S. Botelho

Wildfire hazard abatement is one of the major reasons to use prescribed burning. Computer simulation, case studies, and analysis of the fire regime in the presence of active prescribed burning programs in forest and shrubland generally indicate that this fuel management tool facilitates fire suppression efforts by reducing the intensity, size and damage of wildfires. However, the conclusions that can be drawn from the above approaches are limited, highlighting the need for more properly designed experiments addressing this question. Fuel accumulation rate frequently limits prescribed fire effectiveness to a short post-treatment period (2–4 years). Optimisation of the spatial pattern of fire application is critical but has been poorly addressed by research, and practical management guidelines are lacking to initiate this. Furthermore, adequate treatment efforts in terms of fire protection are constrained by operational, social and ecological issues. The best results of prescribed fire application are likely to be attained in heterogeneous landscapes and in climates where the likelihood of extreme weather conditions is low. Conclusive statements concerning the hazard-reduction potential of prescribed fire are not easily generalised, and will ultimately depend on the overall efficiency of the entire fire management process.


2012 ◽  
Vol 39 (8) ◽  
pp. 731 ◽  
Author(s):  
Ben Hope

Context Prescribed burning is routinely performed within the Sydney Basin as a method of fire-hazard mitigation. Despite the widespread use of prescribed fire, knowledge of the impact of prescribed fire on most fauna species remains unclear. This is particularly the case for bandicoot species. Aims To determine the impact of a low-intensity prescribed fire on the survival of the long-nosed bandicoot, Perameles nasuta, and the southern brown bandicoot, Isoodon obesulus obesulus (hereafter abbreviated to I. obesulus), immediately after the fire and at 5 weeks, 5 months and 13 months following the fire. To document the spatial ecology and nesting requirements of I. obesulus and P. nasuta before and after fire. Methods One I. obesulus and seven P. nasuta (five female and two male) individuals were radio-tracked. Animals were tracked before, during and following a hazard-reduction burn to assess the impact of fire on home range, survival and nesting behaviour. Key results Post-fire survival of P. nasuta and I. obesulus was high and the population remained stable up to 5 months following the fire. All animals tracked within the burn area (three female P. nasuta) survived the passage of fire. The home range for one male I. obesulus was found to be 2.35 ha 50% kernel-density estimate (KDE) and 12.35 ha 95% KDE. Female P. nasuta (n = 5) had a home range of 1.3 ha ± 0.2 s.e. 50% KDE and 7.5 ha ± 1.7 s.e. 95% KDE. Male P. nasuta (n = 1) had a home range of 1.1 ha 50% KDE and 6.5ha 95% KDE. Nesting for both species tended to occur in dense vegetation, with a slight shift to non-combustible refuge sites post-fire. Animals tended to maintain exclusive and relatively stable core home ranges, although overlap of non-core home ranges was common. Conclusions The survival of bandicoots following a low-intensity hazard-reduction fire was high in the short term; however, further research is required to determine how the components of a fire regime affect native species, in particular peramelids. Implications Hazard-reduction fires should be used with caution to manage the isolated and endangered northern Sydney population of I. obesulus, so as to ensure the persistence of this species.


2007 ◽  
Vol 16 (5) ◽  
pp. 531 ◽  
Author(s):  
Patrice Savadogo ◽  
Didier Zida ◽  
Louis Sawadogo ◽  
Daniel Tiveau ◽  
Mulualem Tigabu ◽  
...  

Fuel characteristics, fire behaviour and temperature were studied in relation to grazing, dominant grass type and wind direction in West African savanna–woodland by lighting 32 prescribed early fires. Grazing significantly reduced the vegetation height, total fuel load, and dead and live fuel fractions whereas plots dominated by perennial grasses had higher values for vegetation height, total fuel load and the quantity of live fuel load. Although fire intensity remained insensitive (P > 0.05) to any of these factors, fuel consumption was significantly (P = 0.021) reduced by grazing, rate of spread was faster in head fire (P = 0.012), and flame length was shorter in head fire than back fire (P = 0.044). The average maximum temperature was higher (P < 0.05) on non-grazed plots, on plots dominated by annual grasses, on plots subjected to head fire, and at the soil surface. Lethal temperature residence time showed a nearly similar trend to fire temperature. Wind speed and total fuel load were best predictors of fire behaviour parameters (R2 ranging from 0.557 to 0.862). It can be concluded that grazing could be used as a management tool to modify fire behaviour, back fire should be carried out during prescribed burning to lower fire severity, and the fire behaviour models can be employed to guide prescribed early fire in the study area.


2010 ◽  
Vol 16 (1) ◽  
pp. 46 ◽  
Author(s):  
T. D. Penman ◽  
S. H. Penman

Prescribed burning is applied worldwide as a forest management tool. It is broadly accepted that altered fire regimes can directly impact upon community structure and composition, but little is known about the indirect effects of altered fire regimes on the mechanisms that produce community-level changes such as changes to the reproductive output of individual plants, hence populations. We examined the reproductive output of four species of Proteaceae within a long term study site where disturbance histories for the last twenty years have been accurately recorded on 216 plots. Frequent fire was found to increase woody fruit production in Banksia marginata, but had no apparent effect on B. serrata, Hakea eriantha or H. sericea. Results of this study vary from a similar study which examined the effect of wildfires. The differences observed are likely to reflect the differing impacts of fire intensity on these species. Indirect changes in fruit production may result in changes in reproductive success of species which in turn may affect vegetation community structure and faunal habitat.


Koedoe ◽  
2013 ◽  
Vol 55 (1) ◽  
Author(s):  
Tineke Kraaij ◽  
Richard M. Cowling ◽  
Brian W. Van Wilgen

Until recently, fire ecology was poorly understood in the eastern coastal region of the Cape Floral Kingdom (CFK), South Africa. Rainfall in the area is aseasonal and temperatures are milder than in the winter-rainfall and drier inland parts of the CFK, with implications for the management of fire regimes. We synthesised the findings of a research programme focused on informing ecologically sound management of fire in eastern coastal fynbos shrublands and explored potential east–west trends at the scales of study area and CFK in terms of fire return interval (FRI) and fire season. FRIs (8–26 years; 1980–2010) were comparable to those elsewhere in the CFK and appeared to be shorter in the eastern Tsitsikamma than in the western Outeniqua halves of the study area. Proteaceae juvenile periods (4–9 years) and post-fire recruitment success suggested that for biodiversity conservation purposes, FRIs should be ≥ 9 years in eastern coastal fynbos. Collectively, findings on the seasonality of actual fires and the seasonality of fire danger weather, lightning and post-fire proteoid recruitment suggested that fires in eastern coastal fynbos are not limited to any particular season. We articulated these findings into ecological thresholds pertaining to the different elements of the fire regime in eastern coastal fynbos, to guide adaptive management of fire in the Garden Route National Park and elsewhere in the region.Conservation implications: Wildfires are likely to remain dominant in eastern coastal fynbos, whilst large-scale implementation of prescribed burning is unattainable. Fires occurring in any season are not a reason for concern, although other constraints remain: the need for sufficient fire intensity, safety requirements, and integration of fire and invasive alien plant management.


2012 ◽  
Vol 3 (1) ◽  
pp. 142-149 ◽  
Author(s):  
Donald J. Brown ◽  
Bei DeVolld ◽  
Weston H. Nowlin ◽  
Michael R.J. Forstner

Abstract The red imported fire ant Solenopsis invicta (RIFA) is an invasive species found throughout the southern and southeastern United States. Since its introduction, RIFA has been shown to negatively affect a wide range of native vertebrate and invertebrate species. The purposes of this study were to delineate the annual RIFA activity pattern, investigate the association between overstory canopy cover and RIFA captures, and evaluate the effects of low-intensity prescribed fire around pond edges on RIFA in the Lost Pines ecoregion of Texas, a region that provides habitat for most of the remaining endangered Houston toads Bufo houstonensis. We found that annual RIFA activity followed a quadratic curve, with above-average activity between May and October. We found an inverse relationship between mean percentage of canopy cover near pond edges and mean number of RIFA captured. We found that low-intensity prescribed burning had no significant influence on RIFA captures during our study period. However, strong spatial and temporal capture variability was apparent, and thus a strong impact would have been necessary to detect an effect. Although this study provides evidence that should decrease concerns that wildlife managers, conservation biologists, and landowners in the Lost Pines ecoregion may have about exacerbating RIFA abundance when using fire as an ecosystem management tool, we recommend additional work be conducted using a greater sample size, greater sampling effort, and longer study duration. We found that RIFA activity was highest during the time frame in which juvenile Houston toads emerge from ponds. Thus, RIFA control may be a useful Houston toad recovery tool where breeding ponds are not within dense canopy habitats.


Agronomy ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 340 ◽  
Author(s):  
Xavier Úbeda ◽  
Meritxell Alcañiz ◽  
Gonzalo Borges ◽  
Luis Outeiro ◽  
Marcos Francos

The abandonment of the economic activities of agriculture, livestock, and forestry since the second half of the 20th century, in conjunction with the exodus of inhabitants from rural areas, has resulted in an increase in the forest mass as well as an expansion of forest areas. This, in turn, has led to a greater risk of forest fires and an increase in the intensity and severity of these fires. Moreover, these forest masses represent a fire hazard to adjacent urban areas, which is a problem illustrated here by the village of Capafonts, whose former agricultural terraces have been invaded by shrubs, and which in the event of fire runs the risk of aiding the propagation of the flames from the forest to the village’s homes. One of the tools available to reduce the amount of fuel in zones adjoining inhabited areas is prescribed burns. The local authorities have also promoted measures to convert these terraces into pasture; in this way, the grazing of livestock (in this particular instance, goats) aims to keep fuel levels low and thus reduce the risk of fire. The use of prescribed fires is controversial, as they are believed to be highly aggressive for the soil, and little is known about their long-term effects. The alternation of the two strategies is more acceptable—that is, the use of prescribed burning followed by the grazing of livestock. Yet, similarly little is known about the effects of this management sequence on the soil. As such, this study seeks to examine the impact of the management of the abandoned terraces of Capafonts by means of two prescribed fires (2000 and 2002), which were designed specifically to prevent forest fires from reaching the village. Following these two prescribed burns, a herd of goats began to graze these terraces in 2005. Here, we report the results of soil analyses conducted during this period of years up to and including 2017. A plot comprising 30 sampling points was established on one of the terraces and used to monitor its main soil quality properties. The data were subject to statistical tests to determine whether the recorded changes were significant. The results show modifications to the concentration of soil elements, and since the first prescribed burn, these changes have all been statistically significant. We compare our results with those reported in other studies that evaluate optimum soil concentrations for the adequate growth of grazing to feed goats, and conclude that the soil conditions on the terrace after 17 years are optimum for livestock use.


2000 ◽  
Vol 48 (1) ◽  
pp. 71 ◽  
Author(s):  
David A. Morrison ◽  
John A. Renwick

Fire is a common source of change for the plant species of Mediterranean-type ecosystems, but little is known about the comparative effects of different fire intensities. Accordingly, nine species of small tree (Acacia binervia, Acacia implexa, Acacia parramattensis, Casuarina littoralis, Casuarina torulosa, Hakea sericea, Jacksonia scoparia, Leptospermum trinervium, Persoonia linearis) were studied 1 year after each of two low-intensity prescribed fires and a high-intensity wildfire at a site in the outer western region of the Sydney metropolitan area, south-eastern Australia. All of the species except H. sericea proved to be at least partly tolerant of the low-intensity fires (40–80% of their stems surviving the fires), but only C. torulosa, L. trinervium and P. linearis were tolerant of the high-intensity fire (20–30% stem survival). All of the fire-tolerant species had more of their smaller stems killed by the fires, and the high-intensity fire killed larger stems than did the low-intensity-fires. The size of surviving stems was related to the fire-tolerance characteristics for these species, specifically the presence or absence of insulating bark and epicormic or lignotuberous buds, as well as stem height (preventing 100% leaf-scorch). Those species with post-fire shoots at the stem base produced them when the upper part of the stem had been killed, with variable response to the fire intensities in the number of shoots produced. Those species with post-fire epicormic shoots produced them if the stem was alive post-fire, usually with fewer shoots produced after the high-intensity than the low-intensity fire. The number of shoots produced was positively related to the size of the stem for both fire intensities. These different sets of responses to the fire intensities have important implications for the ability to predict community responses to fire based on the study of only a few species, as well for the long-term effects of prescribing a particular fire regime.


2006 ◽  
Vol 15 (1) ◽  
pp. 19 ◽  
Author(s):  
Walter G. Thies ◽  
Douglas J. Westlind ◽  
Mark Loewen ◽  
Greg Brenner

Prescribed burning is a management tool used to reduce fuel loads in western interior forests. Following a burn, managers need the ability to predict the mortality of individual trees based on easily observed characteristics. Astudy was established in six stands of mixed-age ponderosa pine (Pinus ponderosa Dougl. ex Laws.) with scattered western junipers at the south end of the Blue Mountains near Burns, Oregon, USA. Stands were thinned in either 1994 or 1995. Three treatments, a fall burn, a spring burn, and an unburned control, were randomly assigned to 12-ha experimental units within each stand. Prescribed burns occurred during mid-October of 1997 or mid-June of 1998 and were representative of operational burns, given weather and fuel conditions. Within each experimental unit, six 0.2-ha plots were established to evaluate responses to the burns. Ponderosa pine plot trees (n =3415) alive 1 month after the burns were evaluated and observed for four growing seasons. Nine fire damage and tree morphological variables were evaluated by logistic regression. A five-factor full model and a two-factor reduced model are presented for projecting probability of mortality. Significant variables in the full model included measures of crown, bole, and basal damage.


1985 ◽  
Vol 12 (2) ◽  
pp. 141-146 ◽  
Author(s):  
George P. Malanson

Wildland fire management directly affects the forces of natural selection to which plant taxa become adapted. Changes in a fire regime will often result in changes in the relative abundance of particular species, and may cause the extinction of some of them. Life-history characteristics are important indicators of adaptation to recurrent disturbance, such as may be produced by fire. The incorporation of these characteristics in a computer simulation allows of the projection of species abundance under different fire regimes.Through prescribed burning and fire suppression, fire interval and fire intensity can be controlled to some extent. The fire intensity for given sets of fuel, site, and meteoro-logical conditions, representing given fire-intervals, is calculated with the use of a fire behaviour computer simulation. These results are incorporated in computer simulation of the demographic competition of the five dominant shrub species of coastal sage-scrub in the Santa Monica Mountains of southern California: Artemisia californica, Encelia californica, Eriogonum cinereum, Salvia leucophylla, and S. mellifera. The model incorporates resprouting proportions, seedling establishment, and growth, and assumes survivorship rates in simulating scramble competition for space. Foliar cover-values of the five species are projected for nine different fire regimes. Short fire-intervals of the order of 10–20 years, such as might occur under a regime of prescribed burning, may eliminate or greatly reduce some species, whereas longer intervals allow the maintenance of a more diverse community especially of shrubs. Fixed and variable interval-lengths do not produce appreciably different results.This study suggests that prescribed burning at 10–20 years' intervals should not be used indiscriminately to reduce wildland fire hazard in southern California. The fire intervals that will reduce the hazard, may eliminate some dominant native shrub species. A ‘natural’ fire regime which would maintain the natural vegetation while constituting only a minimum hazard to homesites may, unfortunately, be mutually exclusive goals in the coastal sage-scrub of southern California.


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