Article 17 web tool

Scientific name used in original MS report if different than recommended: "Hyla arborea"
Information provided in the field 2.8.2: Since the first half of the 20th century, H.a. has experienced a tremendous decline in both range, habitat area and population size. Although since 2000 some populations have further been lost, the number of calling males steeply increased during the last 10 years, about tenfold, mainly due to specific habitat restoration projects within the existing metapopulations. The flemisch regional conservation objectives not only pursue a further strengthening of these metapopulations against stochastic events, but also an active increase of the number of (meta)populations. The current revival of several populations demonstrates that restoration is generally successful. This is also reflected in the successful re-introduction of the species in the Netherlands, right across the Belgian border. At the Belgian side of the border at these locations, several migrating adults have already been observed, significantly increasing the actual range in Belgium. Hence, future prospects are cautiously – as a pioneer species H.a. shows inherently high fluctuations in population size - judged as positive. However, further restoration will require serious efforts to enhance habitat quality and connectivity in order to maintain a healthy genetic basis. To guarantee its long term presence in the Flemish region, the number of individuals still has to increase in several (meta)populations. Only in a few locations, numbers are high enough to ensure a viable (meta)population (i.e. >2400 ind.). Assuming that about 8 (meta)populations are actually present, the actual regional population size of 5000 ind. is far below what is needed for its regional survival based on its occurrence since 1994 (see 2.4.14b).

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Scientific name used in original MS report if different than recommended: "Hyla arborea"
Information provided in the field 2.8.2: 2.5.9 Area of suitable habitat: Based on the distribution modelled with the software MaxEnt from the values of environmental and climatic variables at known localities for the species. A map of this modelled distribution is attached. 2.3.3 & 2.5.5: Short-term trend period for range and habitat of the species: trend monitoring data correspond to the reported periods. No data are available for the required periods. 2.5.9 Area of suitable habitat: Based on the distribution modelled with the software MaxEnt from the values of environmental and climatic variables at known localities for the species. A map of this modelled distribution is attached.

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Scientific name used in original MS report if different than recommended: "Hyla arborea"
Information provided in the field 2.8.2:

2.3: In 2007 is een range gerapporteerd van 3100km2. De trend is bepaald m.b.v. een Chi-kwadraat toets waarin de situatie uit de vorige rapportageperiode is vergeleken met de huidige. Het verschil is niet significant. De expert geeft echter aan dat er wel degelijk sprake is van een echte uitbreiding. De range voor 2007 is te laag vastgesteld, er is nu een betere data beschikbaar.
2.4: De populatietrend uit het NEM is een sterke toename. In 2007 is een populatiegrootte gerapporteerd van 10.000-15.000 exx. Dit is vermoedelijk een overschatting geweest. De huidige populatieschatting is gebaseerd op intensievere inventarisaties.
2.5: In 2007 is 234 km2 leefgebied gemeld. Er is een echte toename, het verschil met de vorige rapportage komt door betere kennis.
De belangrijkste reden waarom de staat van instandhouding is veranderd van zeer ongunstig in 2007 naar gunstig nu is een werkelijke vooruitgang van de soort. Met de huidige FRR en FRP zouden de beoordelingen van range en populatiein 2007 ook gunstiger (ten minste matig ongunstig) zijn geweest.

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