Long-term record of defoliation intensity in monitoring plots of pine woodland by the pine processionary moth (Thaumetopoea pityocampa)

Data Records

The data in this occurrence resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 4,851 records.

1 extension data tables also exist. An extension record supplies extra information about a core record. The number of records in each extension data table is illustrated below.

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.

Versions

The table below shows only published versions of the resource that are publicly accessible.

How to cite

Researchers should cite this work as follows:

Hódar Correa J A (2023). Long-term record of defoliation intensity in monitoring plots of pine woodland by the pine processionary moth (Thaumetopoea pityocampa). Version 1.0. Sierra Nevada Global Change Observatory. Andalusian Environmental Center, University of Granada, Regional Government of Andalusia. Occurrence dataset. https://doi.org/10.15470/osdlte

Rights

Researchers should respect the following rights statement:

The publisher and rights holder of this work is Sierra Nevada Global-Change Observatory (UGR-JA). This work is licensed under a Creative Commons Attribution (CC-BY 4.0) License.

GBIF Registration

This resource has been registered with GBIF, and assigned the following GBIF UUID: c2d4e314-3346-419d-8dfc-e9eff4ee0038.  Sierra Nevada Global-Change Observatory (UGR-JA) publishes this resource, and is itself registered in GBIF as a data publisher endorsed by GBIF Spain.

Keywords

Occurrence; Mediterranean pine forests; pine woodland; pine processionary moth; defoliation

Contacts

Geographic Coverage

All the plots are located in the southeast of the Iberian Peninsula, mostly in the Granada province. There are some preselected plots in the province of Almería, but most of them have no data recorded so far. The plots were chosen trying to cover as much as possible the diversity of pine woodlands in which the pine processionary moth is present. The altitudinal range covers from sea level to 2500 m altitude, from coastal areas to high mountains and inland depressions, and pine forests can be natural, spontaneous regeneration, or the result of plantations.

Taxonomic Coverage

The dataset is centred on population size and defoliation intensity by the pine processionary moth (Thaumetopoea pityocampa, Notodontidae, Lepidoptera). Sampling units are individually labelled pines, belonging to seven different tree species: Pinus pinea, Pinus halepensis, Pinus pinaster, Pinus nigra, Pinus sylvestris, Pinus uncinata and Pinus canariensis.

Temporal Coverage

Project Data

1-The Sierra Nevada Global-Change Observatory (https://obsnev.es/) is an ambitious project promoted by the Department of Sustainability, Environment and Blue Economy of the Regional Government of Andalusia with the scientific coordination of the University of Granada, in order to monitor the effects of global change in the Sierra Nevada protected area. For this purpose, the Sierra Nevada Global-Change Observatory has developed a monitoring programme and an information system for appropriate data management. 2-Smart EcoMountains (University of Granada-Sierra Nevada, Spain) is the Thematic Center on Mountain Ecosystems of the European Research Infrastructure LifeWatch-ERIC (https://smartecomountains.lifewatch.eu/). The main objective of the project is the long-term evaluation of mountain ecosystems' functions and services in the context of global change, using remote sensing, computing and new information and communication technologies advanced tools. The Smart EcoMountains project pursues three main objectives: 1) generate information on biodiversity, ecosystem services and global change in mountain ecosystems; 2) develop new technological tools and services that facilitate the exchange, localisation, access and analysis of data by scientists, in order to improve our knowledge of mountain ecosystems and the main global change processes affecting them; 3) develop tools to inform society about the most important global change processes affecting mountain biodiversity and ecosystem services, and support environmental managers and policymakers in science-based decision making. 3- Survival of an ectothermal organism requires that development and reproduction be synchronized with the appropriate periods of the annual cycle, and those inadequate with the phases of inactivity, but the sum of the times required for all phases of the life cycle cannot exceed one year in univoltine species. The problem we are going to unravel in this project is to understand if variation in the phenological strategy of the pine processionary moth (Thaumetopoea pityocampa) along an altitudinal gradient responds to an optimization of the pupation length, dragging as a consequence the rest of the cycle, or if on the contrary, it aims to diversify the possibility of avoiding predators and parasites, tracking a less optimal but broader period and playing with the climatic variety between years. Answering this question implies to understand what factors regulate the pupation length of the processionary and how non-climatic selective pressures (mainly predators and parasitoids) vary in each environment of the gradient. The study consists of three blocks: an observational one, designed to collect basic information about the species along the gradient; an experimental one, aimed at unravel what abiotic and, above all, biotic factors influence the phenology of the phase of the life cycle most difficult to observe, which is the pupa stage; and one of simulation, in which we will test our ability to predict the life cycle of the processionary, based on the observational and experimental data collected, through an ABM (Agent-Based Model). Although this project is primarily of basic research, its results will be important for the conservation and management of biodiversity in forest ecosystems. 4- The pine processionary moth (Thaumetopoea pityocampa, PPM) is a known defoliator alternating in its population dynamics periods at very low densities with periods of overpopulation, causing strong defoliation in the pine forests where it lives. The causes of this population dynamics have been attributed to abiotic (climate), biotic (predation, quantity and quality of food) factors, or both, with generally inconclusive results. The hypothesis that this project intends to explore is that PPM outbreaks are triggered by different causes in different places: although they share a development habitat (homogeneous pine forests) and a precondition in the biological features of the PPM (high reproductive investment, gregariousness), outbreaks start in "window of opportunity" in which group size and larval survival give each other positive feedback. To do this, we will take advantage of the different conditions that the PPM experiences along the altitude gradient of Sierra Nevada, in which previous data suggest that the "windows of opportunity" depend on climatic factors in the upper part of the gradient and biotic factors in the lower one. The study comprises of four blocks. First, we will use the Andalusian Government's database of PPM monitoring (1993-2019) to compare the characteristics of plots with highly contrasted PPM incidence histories. Second, we will quantify the predation rates in the successive life phases of the PPM by different types of predators (egg parasitoids, pupal parasitoids, birds and bats) in several plots that intensively monitored from 2015, distributed along the altitude gradient of the Sierra Nevada. Third, we will analyze, by means of experimental manipulations of the density of egg batch, the effect that the aggregation of egg batches has on the oviposition behavior of the moths, the predation rate and, later, the larval survival. Fourth, we will modify the bird density in a pine forest plot by placing nesting boxes, in order to determine if they are really able to control the PPM population. Although this project is eminently basic research, the results obtained will have significance for the conservation and management of biodiversity in forest ecosystems.

The personnel involved in the project:

Sampling Methods

Pines were visited every winter, and percentage of defoliation, estimated by eye from two perpendicular sides, was recorded. From 2014, also number of Pine Processionary Moth winter tents was recorded. Data were registered at the end of the period of caterpillar activity, February-April depending on the plot altitude and winter climatic conditions. The height of the pines was estimated by eye in 1998, when initially labelled. After that, in 2021 all trees were revisited, georeferenced, its height measured by a clinometre, DBH measured with a measuring tape, and some additional data on the shape of the canopy were also recorded.

Method step description:

1. 1. Field sampling (see Sampling Description section). 2. Data is stored in Linaria (https://linaria.obsnev.es/), the institutional data repository of the Sierra Nevada Global-Change Observatory. 3. The dataset was standardised to the Darwin Core structure as occurrence data. It contains, specifically: 4,851 occurrences, and 35,474 records of associated measurements of 9 variables: “Percentage of defoliation caused by pine processionary moth”, "Number of pine processionary moth nests for that winter", "Height of the pine tree", "Diametre at breast height", "Tree top diametre", "Tree top shape", "Height of the unbranched part of the trunk of the tree measured from the ground to the first branches", "Number of neighbouring trees within a radius of 5 metres", "Year of the death of the tree". The Darwin Core elements included in the Occurrence Core are: occurrenceID, eventID, catalogNumber, collectionCode, datasetName, institutionCode, ownerInstitutionCode, modified, language, license, eventDate, year, basisOfRecord, recordedBy, recordedByID, individualCount, scientificName, taxonRank, kingdom, phylum, class, order, family, genus, specificEpithet, scientificNameAuthorship, continent, country, countryCode, locality, minimumElevationInMeters, maximumElevationInMeters, samplingProtocol, decimalLatitude, decimalLongitude, geodeticDatum, coordinateUncertaintyInMeters, habitat. For the Measurement or Fact Extension file, the Darwin Core elements included are: measurementID, occurrenceID, measurementType, measurementValue, measurementUnit, measurementMethod, measurementdetermineddate. 4. The resulting dataset was published through the Integrated Publishing Toolkit of the Spanish node of the Global Biodiversity Information Facility (GBIF) (http://ipt.gbif.es).

Additional Metadata