Long-Term Monitoring of Amphibian Populations of a National Park in Northern Spain Reveals Negative Persisting Effects of Ranavirus, but Not Batrachochytrium dendrobatidis

Amphibians are the most highly threatened vertebrates, and emerging pathogens are a serious threat to their conservation. Amphibian chytrid fungi and the viruses of the Ranavirus genus are causing disease outbreaks worldwide, including in protected areas such as National Parks. However, we lack information about their effect over amphibian populations in the long-term, and sometimes these mortality episodes are considered as transient events without serious consequences over longer time-spans. Here, we relate the occurrence of both pathogens with the population trends of 24 amphibian populations at 15 sites across a national Park in northern Spain over a 14-year period. Just one out 24 populations presents a positive population trend being free of both pathogens, while seven populations exposed to one or two pathogens experienced strong declines during the study period. The rest of the study populations (16) remain stable, and these tend to be of species that are not susceptible to the pathogen present or are free of pathogens. Our study is consistent with infectious diseases playing an important role in dictating amphibian population trends and emphasizes the need to adopt measures to control these pathogens in nature. We highlight that sites housing species carrying Ranavirus seems to have experienced more severe population-level effects compared to those with the amphibian chytrid fungus, and that ranaviruses could be just as, or more important, other more high-profile amphibian emerging pathogens.

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Single infection with Batrachochytrium dendrobatidis or Ranavirus does not increase probability of co-infection in a montane community of amphibians

Scientific Reports ◽

10.1038/s41598-020-78196-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jaime Bosch ◽

Camino Monsalve-Carcaño ◽

Stephen J. Price ◽

Jon Bielby

Keyword(s):

Batrachochytrium Dendrobatidis ◽

Disease Outbreaks ◽

Single Infection ◽

Chytrid Fungus ◽

Population Declines ◽

Emerging Pathogens ◽

Amphibian Species ◽

Management Interventions ◽

Amphibian Chytrid Fungus ◽

Common Situation

AbstractUnderstanding the occurrence and consequence of co-infections can be useful in designing disease management interventions. Amphibians are the most highly threatened vertebrates, and emerging pathogens are a serious threat to their conservation. The amphibian chytrid fungus and the viruses of the Ranavirus genus are already widely distributed, causing disease outbreaks and population declines worldwide. However, we lack information about the occurrence and consequences of coinfection with these pathogens across age-classes of amphibian hosts. Here, we analyze the occurrence of infection of the amphibian chytrid fungus and ranaviruses during one season in two susceptible amphibian species at two different locations at which outbreaks have occurred. We found that the co-occurrence of both pathogens in a particular host is not common except in highly susceptible life-stages, and that single infections are the most common situation. Moreover, we found that the occurrence of one pathogen in a particular host did not predict the occurrence of the other. We attribute these results to the niches in which both pathogens proliferate in amphibian hosts.

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Temporal Evolution of Immunity Distributions in a Population with Waning and Boosting

Complexity ◽

10.1155/2018/9264743 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13

Author(s):

M. V. Barbarossa ◽

M. Polner ◽

G. Röst

Keyword(s):

Mathematical Model ◽

Steady State ◽

Temporal Evolution ◽

Disease Outbreaks ◽

Population Level ◽

Coupled System ◽

Disease Outbreak ◽

Periodic Disease ◽

Evolution Of Immunity

We investigate the temporal evolution of the distribution of immunities in a population, which is determined by various epidemiological, immunological, and demographical phenomena: after a disease outbreak, recovered individuals constitute a large immune population; however, their immunity is waning in the long term and they may become susceptible again. Meanwhile, their immunity can be boosted by repeated exposure to the pathogen, which is linked to the density of infected individuals present in the population. This prolongs the length of their immunity. We consider a mathematical model formulated as a coupled system of ordinary and partial differential equations that connects all these processes and systematically compare a number of boosting assumptions proposed in the literature, showing that different boosting mechanisms lead to very different stationary distributions of the immunity at the endemic steady state. In the situation of periodic disease outbreaks, the waveforms of immunity distributions are studied and visualized. Our results show that there is a possibility to infer the boosting mechanism from the population level immune dynamics.

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Estimating population sizes of lions Panthera leo and spotted hyaenas Crocuta crocuta in Uganda's savannah parks, using lure count methods

Oryx ◽

10.1017/s0030605313000112 ◽

2013 ◽

Vol 48 (3) ◽

pp. 394-401 ◽

Cited By ~ 11

Author(s):

Edward Okot Omoya ◽

Tutilo Mudumba ◽

Stephen T. Buckland ◽

Paul Mulondo ◽

Andrew J. Plumptre

Keyword(s):

National Parks ◽

Protected Area ◽

National Park ◽

Crocuta Crocuta ◽

Panthera Leo ◽

Analysis Method ◽

Conservation Areas ◽

Conservation Area ◽

Population Sizes

AbstractDespite > 60 years of conservation in Uganda's national parks the populations of lions and spotted hyaenas in these areas have never been estimated using a census method. Estimates for some sites have been extrapolated to other protected areas and educated guesses have been made but there has been nothing more definitive. We used a lure count analysis method of call-up counts to estimate populations of the lion Panthera leo and spotted hyaena Crocuta crocuta in the parks where reasonable numbers of these species exist: Queen Elizabeth Protected Area, Murchison Falls Conservation Area and Kidepo Valley National Park. We estimated a total of 408 lions and 324 hyaenas for these three conservation areas. It is unlikely that other conservation areas in Uganda host > 10 lions or > 40 hyaenas. The Queen Elizabeth Protected Area had the largest populations of lions and hyaenas: 140 and 211, respectively. It is estimated that lion numbers have declined by 30% in this protected area since the late 1990s and there are increasing concerns for the long-term viability of both species in Uganda.

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Vegetation change (1988–2010) in Camdeboo National Park (South Africa), using fixed-point photo monitoring: The role of herbivory and climate

Koedoe ◽

10.4102/koedoe.v55i1.1127 ◽

2013 ◽

Vol 55 (1) ◽

Cited By ~ 5

Author(s):

Mmoto L. Masubelele ◽

Michael T. Hoffman ◽

William Bond ◽

Peter Burdett

Keyword(s):

South Africa ◽

Fixed Point ◽

National Parks ◽

Vegetation Cover ◽

National Park ◽

Vegetation Change ◽

Growth Form ◽

Annual Rainfall ◽

Management Interventions

Fixed-point photo monitoring supplemented by animal census data and climate monitoring potential has never been explored as a long-term monitoring tool for studying vegetation change in the arid and semi-arid national parks of South Africa. The long-term (1988–2010), fixed-point monitoring dataset developed for the Camdeboo National Park, therefore, provides an important opportunity to do this. Using a quantitative estimate of the change in vegetation and growth form cover in 1152 fixed-point photographs, as well as series of step-point vegetation surveys at each photo monitoring site, this study documented the extent of vegetation change in the park in response to key climate drivers, such as rainfall, as well as land use drivers such as herbivory by indigenous ungulates. We demonstrated the varied response of vegetation cover within three main growth forms (grasses, dwarf shrubs [< 1 m] and tall shrubs [> 1 m]) in three different vegetation units and landforms (slopes, plains, rivers) within the Camdeboo National Park since 1988. Sites within Albany Thicket and Dwarf Shrublands showed the least change in vegetation cover, whilst Azonal vegetation and Grassy Dwarf Shrublands were more dynamic. Abiotic factors such as drought and flooding, total annual rainfall and rainfall seasonality appeared to have the greatest influence on growth form cover as assessed from the fixed-point photographs. Herbivory appeared not to have had a noticeable impact on the vegetation of the Camdeboo National Park as far as could be determined from the rather coarse approach used in this analysis and herbivore densities remained relatively low over the study duration.Conservation implications: We provided an historical assessment of the pattern of vegetation and climatic trends that can help evaluate many of South African National Parks’ biodiversity monitoring programmes, especially relating to habitat change. It will help arid parks in assessing the trajectories of vegetation in response to herbivory, climate and management interventions.

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Is overwintering mortality driving enigmatic declines? Evaluating the impacts of trematodes and the amphibian chytrid fungus on an anuran from hatching through overwintering

PLoS ONE ◽

10.1371/journal.pone.0262561 ◽

2022 ◽

Vol 17 (1) ◽

pp. e0262561

Author(s):

Olivia Wetsch ◽

Miranda Strasburg ◽

Jessica McQuigg ◽

Michelle D. Boone

Keyword(s):

Batrachochytrium Dendrobatidis ◽

Species Conservation ◽

Emerging Infectious Diseases ◽

The Novel ◽

Chytrid Fungus ◽

Growth And Survival ◽

Critical Life Events ◽

Overwintering Mortality ◽

Amphibian Chytrid Fungus

Emerging infectious diseases are increasing globally and are an additional challenge to species dealing with native parasites and pathogens. Therefore, understanding the combined effects of infectious agents on hosts is important for species’ conservation and population management. Amphibians are hosts to many parasites and pathogens, including endemic trematode flatworms (e.g., Echinostoma spp.) and the novel pathogenic amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]). Our study examined how exposure to trematodes during larval development influenced the consequences of Bd pathogen exposure through critical life events. We found that prior exposure to trematode parasites negatively impacted metamorphosis but did not influence the effect of Bd infection on terrestrial growth and survival. Bd infection alone, however, resulted in significant mortality during overwintering—an annual occurrence for most temperate amphibians. The results of our study indicated overwintering mortality from Bd could provide an explanation for enigmatic declines and highlights the importance of examining the long-term consequences of novel parasite exposure.

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Impacts of national parks on tourism: a case study from a prominent alpine national park

ECONOMICS AND POLICY OF ENERGY AND THE ENVIRONMENT ◽

10.3280/efe2008-003005 ◽

2009 ◽

pp. 103-120

Author(s):

Michael Getzner

Keyword(s):

Development Strategy ◽

National Parks ◽

National Park ◽

Tourism Development ◽

Positive Trend ◽

The Difference ◽

The Impact ◽

Overnight Stays

-National parks and other categories of protected areas are often assumed to enhance regional economic development due to park tourism. The current study attempts to estimate the impact of the Hohe Tauern national park (Austria) on tourism by exploring whether and to what extent the national park may have had an influence on tourism development. For most national park communities, the results suggest that the establishment of the national park had some impact by enforcing an already positive trend or by weakening or reversing a negative trend of tourism. However, breakpoint tests exhibit turning points up to several years after the establishment of the park, indicating that taking a national park as the basis for tourism development is a medium to long term development strategy. In the short term, the impact of a national park on tourism is not measurable. Tourism increased by 1 to 3% annually after the breakpoint, indicating that the establishment of a national park has to be incorporated into the tourism and development strategy of a region right from the start. The causal relationship between the establishment of the national park and tourism development may be weak, in particular in communities where the difference between the actual and the forecast numbers of overnight stays is small. Marketing national park tourism and building up a brand or distinctive label may therefore contribute to regional development particularly in the long term.Key words: Tourism, national park, protected area, time series, stationarity, breakpoint test, ARIMA.JEL classifications: R110, L830, C220.Parole chiave: Turismo, parco nazionale, area protetta, serie temporale, stazionarietŕ, test di breakpoint, ARIMA.

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WildCountry

Pacific Conservation Biology ◽

10.1071/pc030221 ◽

2002 ◽

Vol 8 (4) ◽

pp. 221 ◽

Cited By ~ 4

Author(s):

Harry F. Recher

Keyword(s):

Nature Conservation ◽

National Parks ◽

National Park ◽

Nature Reserve ◽

New South ◽

New South Wales ◽

Term Survival ◽

South Wales ◽

Reserve System

REGARDLESS of the merits and values of individual national parks and nature reserves, Australia's conservation reserves do not ensure the survival of the continent's biota. There are many reasons for this. Reserves, even the largest, are too small and vulnerable to broad area disturbance. Consider that, in January 2003, fires burnt more than two-thirds of Kosciuszko National Park, which at 690 000 ha is the largest park in New South Wales and one of the largest in Australia. This shows how even the largest conservation reserves are at risk of catastrophic disturbance. The much smaller Nadgee Nature Reserve (21 000 ha) in southeastern New South Wales has burnt almost in its entirety twice in the 35 years I have worked there. The Nadgee fires and those in Kosciuszko were started by lightning and were the result of prolonged drought, events common across the continent. When small size is coupled with isolation, the long-term survival of populations and the exchange of propagules within the reserve system becomes problematical. Small size and isolation do not leave much scope for plants and animals to adapt to long-term climate change, either through dispersal or by evolution. Even reserving 10 or 15% of land for nature conservation, as recommended by some international conservation agencies, will be inadequate; a target of 30% would have better ecological credentials, but even this could prove inadequate unless the nature conservation reserve system was designed to allow for long-term evolutionary change, which it is not (see Archer 2002; Recher 2002a,b).

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Impact of Recreational Activities on an Unmanaged Alpine Campsite: The Case of Kuro-Dake Campsite, Daisetsuzan National Park, Japan

Environments ◽

10.3390/environments6030034 ◽

2019 ◽

Vol 6 (3) ◽

pp. 34 ◽

Cited By ~ 1

Author(s):

Ting Wang ◽

Teiji Watanabe

Keyword(s):

National Parks ◽

National Park ◽

Surface Condition ◽

Ground Surface ◽

Secondary Data ◽

Aerial Photographs ◽

Topographic Map ◽

Questionnaire Surveys ◽

Reservation System

The Kuro-dake Campsite in Daisetsuzan National Park is situated in a fragile alpine setting. Since it opened in 1992, it has not been under formal management. With camping increasingly affecting the Kuro-dake Campsite, this study aims to gain deeper insights into the soil erosion and overcrowding at the campsite and to suggest a corresponding strategy for future management. A detailed topographic map was created using pole photogrammetry to understand the ground surface condition of the campsite in 2017. Aerial photographs taken in 2012 and 2017 were used to understand the long-term changes in the ground surface. Furthermore, questionnaire surveys with campers, interview surveys with organizations related to the park management and secondary data collection were conducted. Two gullies were identified on the topographic map of the campsite. From 2012 to 2017, the campsite size increased by 48 m2. The daily-use level on busy days is nearly seven times the mean daily-use level for the year. Some campers illegally pitch tents on nearby trails on such busy days. The questionnaire surveys in 2017 and 2018 (n = 346) show that most respondents oppose a future closure of the campsite and two-thirds oppose a use limit. The 2018 survey (n = 210) shows that 71% of respondents were not aware of the reservation system in national parks elsewhere; however, 76% agreed to a reservation system to secure their tent space. Introducing formal management oversight, along with a reservation system, is urgently needed.

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