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Global conservation policy and action have largely neglected protecting and monitoring genetic diversity—one of the three main pillars of biodiversity. Genetic diversity (diversity within species) underlies species’ adaptation and survival, ecosystem resilience, and societal innovation. The low priority given to genetic diversity has largely been due to knowledge gaps in key areas, including the importance of genetic diversity and the trends in genetic diversity change; the perceived high expense and low availability and the scattered nature of genetic data; and complicated concepts and information that are inaccessible to policymakers. However, numerous recent advances in knowledge, technology, databases, practice, and capacity have now set the stage for better integration of genetic diversity in policy instruments and conservation efforts. We review these developments and explore how they can support improved consideration of genetic diversity in global conservation policy commitments and enable countries to monitor, report on, and take action to maintain or restore genetic diversity.

Wolves have become increasingly common in the Netherlands since 2015, and since 2019 the country has once again been home to a pack of wolves with young – the first in around 150 years. The government intends to review the current Interprovincial Wolf Plan, a process that will start in 2021. This report provides an answer to 25 research questions formulated by the government. These questions relate to five themes: (1) distribution, occurrence, origin and ecological carrying capacity; (2) behaviour and the relationship between wolves and humans; (3) policy, damage, monitoring and management; (4) ecology; (5) genetic techniques and data exchange in Europe. The latest insights from scientific research and monitoring programmes have been used to answer these questions. The knowledge presented in this report can be used to make scientifically substantiated policy choices with regard to wolves.

Since 2015 wolves more often visit the Netherlands and since 2019 the first pack was a fact including a litter with cubs, the first since 150 years. Although there is already a management plan for wolves, the authorities will start with an update in 2021. This present report contains the answers to 25 questions that were drafted by the authorities. The questions contain five themes: 1: distribution, presence, origin and carrying capacity; 2: behavior and wolf-human relations; 3: policy, damage, monitoring and management, 4: ecology and 5: molecular methods and international exchange of data. The knowledge that was used for answering the questions is based on facts, originating from ongoing monitoring and scientific research. Therefore it can be used to come to motivated policy decisions, Vanaf 2015 komen er weer in toenemende mate wolven voor in Nederland en sinds 2019 is er weer sprake van een roedel met jongen, de eerste in circa 150 jaar. De overheid is voornemens om het huidige interprovinciaal Wolvenplan te herzien, waarmee in 2021 zal worden gestart. In dit voorliggende rapport wordt antwoord gegeven op 25 onderzoeksvragen die zijn opgesteld door de overheid. De vragen hebben betrekking op vijf thema’s, te weten (1) verspreiding, voorkomen, herkomst en ecologische draagkracht; (2) gedrag en wolf-mensrelatie; (3) beleid, schade, monitoring en beheer; (4) ecologie; (5) genetische methodieken en uitwisseling van data in Europa. Voor de beantwoording van deze vragen is gebruikgemaakt van de nieuwste inzichten vanuit wetenschappelijk onderzoek en monitoringsprogramma’s. De kennis die in dit rapport is verzameld, kan worden ingezet voor het maken van wetenschappelijk onderbouwde beleidskeuzes ten aanzien van de wolf.

1. Asian topmouth gudgeon Pseudorasbora parva has been recognized as a highly invasive cyprinid fish species in Europe that can present risk to native fish communities. 2. The present study aimed to investigate whether a native piscivorous fish, pike Esox lucius, is able to reduce the establishment success and invasiveness of topmouth gudgeon Pseudorasbora parva in shallow ponds. We performed a large scale, replicated whole-pond experiment in which ponds were spontaneously colonized by topmouth gudgeon and exposed to experimental native fish communities with and without pike. 3. Our results provide evidence for strong negative effects of pike stocking on the abundance and biomass of topmouth gudgeon, while we found no effects on native fish species. The present study suggests that the presence of native pike can considerably enhance the biotic resistance of fish communities against invasion by topmouth gudgeon. 4. We argue that the resistance of fish communities against invasion by exotic species may in some cases be enhanced by management strategies that reinforce the presence and abundance of naturally occurring and indigenous pike., 1. Asian topmouth gudgeon Pseudorasbora parva has been recognized as a highly invasive cyprinid fish species in Europe that can present risk to native fish communities. 2. The present study aimed to investigate whether a native piscivorous fish, pike Esox lucius, is able to reduce the establishment success and invasiveness of topmouth gudgeon Pseudorasbora parva in shallow ponds. We performed a large scale, replicated whole-pond experiment in which ponds were spontaneously colonized by topmouth gudgeon and exposed to experimental native fish communities with and without pike. 3. Our results provide evidence for strong negative effects of pike stocking on the abundance and biomass of topmouth gudgeon, while we found no effects on native fish species. The present study suggests that the presence of native pike can considerably enhance the biotic resistance of fish communities against invasion by topmouth gudgeon. 4. We argue that the resistance of fish communities against invasion by exotic species may in some cases be enhanced by management strategies that reinforce the presence and abundance of naturally occurring and indigenous pike.

Ponds throughout the world are subjected to a variety of management measures for purposes of biodiversity conservation. Current conservation efforts typically comprise a combination of multiple measures that directly and indirectly impact a wide range of organism groups. Knowledge of the relative impact of individual measures on different taxonomic groups is important for the development of effective conservation programs. We conducted a field study of 28 man-made ponds, representing four management types differing in the frequency of periodic pond drainage and the intensity of fish stock management. We disentangled the relative importance of direct and indirect effects of pond management measures on the community composition of phytoplankton, zooplankton, aquatic macro-invertebrates, submerged and emergent vascular plants. With the exception of phytoplankton, pond management had strong effects on the community composition of all investigated biota. Whether management affected communities directly or indirectly through its impact on fish communities or local environmental conditions in the pond varied between organism groups. Overall, the impact of pond drainage regime and fish community characteristics on the community composition of target organism groups were more important than local environmental conditions. The majority of taxa were negatively associated with fish density, whereas multiple emergent plant species and several taxa of aquatic macro-invertebrates were positively affected by increased drainage frequency. The effects of fish community and drainage tended to be largely independent. The present study indicates that pond drainage is an important element for biodiversity conservation in eutrophicated shallow and interconnected man-made ponds.

Habitatfragmentatie en het verlies daaraan is de belangrijkste oorzaak van biodiversiteitsverlies in Europa. Ecoducten worden ingezet om fragmentatie door wegen te mitigeren en gescheiden populaties weer genetisch te verbinden. Is dat wel efficiënt? In exploratieve simulaties blijken effecten van ecoducten beperkt tot de lokale omgeving. Het succes van een ecoduct staat of valt dus met een zeer doelgerichte inzet en een soortgerichte aanpak. In vele gevallen lijken ecoducten echter niet het meest efficiënte middel voor duurzaam behoud van populaties. Begin 2014 telde Vlaanderen 16.318 ha aan erkende natuurreservaten, tegenover meer dan 20.000 ha aan wegbermen. Nergens in Europa is de fragmentatie van natuur sterker.

We reconstructed the genetic structure of a planktonic crustacean Daphnia longispina living in high mountain lakes and ponds in the Pyrenees to investigate whether it was shaped by persistent founder effects originating shortly after the last glacial maximum or by ongoing dispersal and effective migration (gene flow). We found that the genetic structure can largely be explained by a single colonization event following gradual deglaciation of the Pyrenees c. 10-15 000 years ago. Nuclear genetic diversity declined steeply from southeast to northwest, suggestive of serial colonization of available habitats with advancing deglaciation. The spatial genetic structure suggests that founder effects were major determinants of the presentday diversity, both at the catchment level and at the level of individual water bodies, further supporting extremely low effective migration rates. This study reveals a prime example of a founder effect that is both long-lasting and maintained at small spatial scales. Our data suggest a process of isolation by colonisation as a result of strong priority effects and monopolisation. We found evidence for the spread of haplotypes with Pyrenean ancestry across the Palearctic over distances up to 5500 km, although the local genetic structure after colonization was hardly influenced by contemporary dispersal. Finally, our data also suggest that mitochondrial mutation rates in the studied populations were seven times higher than typically assumed. Overall, we show that founder effects can persist for centuries even at small spatial scales at which the potential for dispersal is high.

Biodiversity and nature values in anthropogenic landscapes often depend on land use practices and management. Evaluations of the association between management and biodiversity remain, however, comparatively scarce, especially in aquatic systems. Furthermore, studies also tend to focus on a limited set of organism groups at the local scale, whereas a multi-group approach at the landscape scale is to be preferred. This study aims to investigate the effect of pond management on the diversity of multiple aquatic organism groups (e.g. phytoplankton, zooplankton, several groups of macro-invertebrates, submerged and emergent macrophytes) at local and regional spatial scales. For this purpose, we performed a field study of 39 shallow man-made ponds representing five different management types. Our results indicate that fish stock management and periodic pond drainage are crucial drivers of pond biodiversity. Furthermore, this study provides insight in how the management of eutrophied ponds can contribute to aquatic biodiversity. A combination of regular draining of ponds with efforts to keep ponds free of fish seems to be highly beneficial for the biodiversity of many groups of aquatic organisms at local and regional scales. Regular draining combined with a stocking of fish at low biomass is also preferable to infrequent draining and lack of fish stock control. These insights are essential for the development of conservation programs that aim long-term maintenance of regional biodiversity in pond areas across Europe., Biodiversity and nature values in anthropogenic landscapes often depend on land use practices and management. Evaluations of the association between management and biodiversity remain, however, comparatively scarce, especially in aquatic systems. Furthermore, studies also tend to focus on a limited set of organism groups at the local scale, whereas a multi-group approach at the landscape scale is to be preferred. This study aims to investigate the effect of pond management on the diversity of multiple aquatic organism groups (e.g. phytoplankton, zooplankton, several groups of macro-invertebrates, submerged and emergent macrophytes) at local and regional spatial scales. For this purpose, we performed a field study of 39 shallow man-made ponds representing five different management types. Our results indicate that fish stock management and periodic pond drainage are crucial drivers of pond biodiversity. Furthermore, this study provides insight in how the management of eutrophied ponds can contribute to aquatic biodiversity. A combination of regular draining of ponds with efforts to keep ponds free of fish seems to be highly beneficial for the biodiversity of many groups of aquatic organisms at local and regional scales. Regular draining combined with a stocking of fish at low biomass is also preferable to infrequent draining and lack of fish stock control. These insights are essential for the development of conservation programs that aim long-term maintenance of regional biodiversity in pond areas across Europe.

A field survey of zooplankton communities was carried out in 32 recently established tropical semi-arid reservoirs in the highlands of Northern Ethiopia with the aim to identify to what extent environmental factors determine species composition of the cladoceran community in such isolated and young reservoirs. To address seasonal variation, the survey was carried out both at the beginning and the end of the dry season. A total of 15 species of cladocerans were identified. Daphnia was the most abundant cladoceran genus, and was present in all reservoirs. Using presence–absence data, no association between cladoceran community composition and geographic distance was found. RDA results indicate that the set of environmental variables that explained cladoceran community composition differed among seasons. Depth, altitude and fish biomass showed a significant association with cladoceran community composition during the wet season, whereas variation in cladoceran community structure was associated with phytoplankton biomass in the dry season. The relative abundance of Daphnia was much higher in the pelagic than in the littoral zone of our study systems. Two key groups of pelagic filter-feeding cladocerans, Diaphanosoma and Daphnia, showed a clear pattern, in which one or the other tended to strongly dominate the community. In addition, we observed a negative association between dominance of Daphnia in the zooplankton community and dominance of cyanobacteria in the phytoplankton community., A field survey of zooplankton communities was carried out in 32 recently established tropical semi-arid reservoirs in the highlands of Northern Ethiopia with the aim to identify to what extent environmental factors determine species composition of the cladoceran community in such isolated and young reservoirs. To address seasonal variation, the survey was carried out both at the beginning and the end of the dry season. A total of 15 species of cladocerans were identified. Daphnia was the most abundant cladoceran genus, and was present in all reservoirs. Using presence–absence data, no association between cladoceran community composition and geographic distance was found. RDA results indicate that the set of environmental variables that explained cladoceran community composition differed among seasons. Depth, altitude and fish biomass showed a significant association with cladoceran community composition during the wet season, whereas variation in cladoceran community structure was associated with phytoplankton biomass in the dry season. The relative abundance of Daphnia was much higher in the pelagic than in the littoral zone of our study systems. Two key groups of pelagic filter-feeding cladocerans, Diaphanosoma and Daphnia, showed a clear pattern, in which one or the other tended to strongly dominate the community. In addition, we observed a negative association between dominance of Daphnia in the zooplankton community and dominance of cyanobacteria in the phytoplankton community.

Biodiversity has a key role in maintaining healthy ecosystems and thereby sustaining ecosystem services to the ever-growing human population. To get an idea of the range of ecosystem services that we use daily, think of how much energy and time it would cost to make Mars (or some other Earth-like planet) hospitable for human life, for example, in terms of atmosphere regulation, freshwater production, soil formation, nutrient cycles, regulation of climate, etc. On our own planet, that process took four billion years and required the contribution of a vast amount of functions performed by different life forms, ultimately driven by evolution and that is only the top of the (melting) iceberg.

Huismussen nemen dramatisch af in West-Europa. Vooral stedelijke populaties raken meer en meer versnipperd en worden kleiner. Zijn deze recente veranderingen reeds voelbaar in de genetische structuur en diversiteit van stedelijke populaties, en leidt dit tot een genetische verarming in stedelijke populaties ten opzichte van het platteland en groenere stadsranden? Of vormen stadsmussen en boerenmussen één pot nat?

Exotische invasieve soorten vormen een reëel probleem voor de biodiversiteit en de economie. Een grote hinderpaal voor een efficiënte preventie en bestrijding van exoten is hun herkenning in een vroeg stadium van de invasie. Sommige soorten exoten zijn met tradionele identificatiethechnieken nauwelijks te onderscheiden van inheemse soorten. Van groene kikkers weten we dat er een handelscircuit bestaat, onder meer voor siervijvers. De herkomst van deze dieren is veelal obscuur (Egyptische', 'Italiaanse'...) en hun lot na importering is slecht bekend, te meer omdat het onderscheid met inheemse soorten zeer moeilijk kan zijn. Aan de hand van genetische identificatie van groene kikkers via DNA-barcodes proberen we na te gaan in welke mate exotische kikkers zich in het wild gevestigd hebben in Vlaanderen, over welke soorten het gaat en wat hun oorsprong is.

In 2010 is er een jaar lang nadrukkelijk aandacht geweest voor biodiversiteit. Opvallend waren de uiteenlopende interpretaties van het begrip biodiversiteit. Het belang van soorten- en ecosysteemdiversiteit wordt door iedereen erkend. Aan de basis van biodiversiteit ligt echter genetische variatie en dit komt minder aan bod. Kennis hierover is nochtans van belang voor het hedendaagse natuurbeheer en een verantwoord duurzaam , natuurgebruik, bijvoorbeeld aangaande vraagstukken als populatiegroottes, herintroducties en translocaties, migratiemogelijkheden, exoten, enz. enerzijds en visserij, jacht, enz. anderzijds. Dit themanummer laat zien welke kennis in inzichten resultaten van genetische onderzoek voor het natuurbeheer kunnen bieden.

Copyright © 2016 Magnolia Press.Species of the genus Daphnia O.F. Müller, 1785 (Cladocera: Daphniidae) have become very important models in evolutionary biology research. Previous morphological and genetic evidence suggests that numerous closely related "species groups" exist within the subgenus Daphnia (Ctenodaphnia) Dybowski & Grochowski, 1895, containing both described and undescribed species. The Daphnia similis group is among these species groups. The aim of the present paper is to revise the taxonomy of the Daphnia (Ctenodaphnia) similis group in the Old World with both morphological and genetic evidence (based on mitochondrial COI and 12S rRNA genes). We found that there are at least four species in the Old World D. similis species group: D. similis Claus, 1876; D. sinensis Gu, Xu, Li, Dumont et Han, 2013; D. similoides Hudec, 1991 and D. inopinata sp. nov. These four taxa of the similis-group, confused previously with D. similis, have different distributional ranges in the Old World, from extremely wide, spanning several biogegraphic regions (as D. sinensis), to regional endemics (D. similoides) and even species known so far from a single locality (D. inopinata sp. nov.). The Daphnia similis group provides another example in the cladocerans whereby the study of males yields more valuable characters for taxonomy than the study of parthenogenetic females.

Copyright © 2016 Magnolia Press.Species of the genus Daphnia O.F. Müller, 1785 (Cladocera: Daphniidae) have become very important models in evolutionary biology research. Previous morphological and genetic evidence suggests that numerous closely related "species groups" exist within the subgenus Daphnia (Ctenodaphnia) Dybowski & Grochowski, 1895, containing both described and undescribed species. The Daphnia similis group is among these species groups. The aim of the present paper is to revise the taxonomy of the Daphnia (Ctenodaphnia) similis group in the Old World with both morphological and genetic evidence (based on mitochondrial COI and 12S rRNA genes). We found that there are at least four species in the Old World D. similis species group: D. similis Claus, 1876; D. sinensis Gu, Xu, Li, Dumont et Han, 2013; D. similoides Hudec, 1991 and D. inopinata sp. nov. These four taxa of the similis-group, confused previously with D. similis, have different distributional ranges in the Old World, from extremely wide, spanning several biogegraphic regions (as D. sinensis), to regional endemics (D. similoides) and even species known so far from a single locality (D. inopinata sp. nov.). The Daphnia similis group provides another example in the cladocerans whereby the study of males yields more valuable characters for taxonomy than the study of parthenogenetic females.

Copyright © 2016 Magnolia Press.Species of the genus Daphnia O.F. Müller, 1785 (Cladocera: Daphniidae) have become very important models in evolutionary biology research. Previous morphological and genetic evidence suggests that numerous closely related "species groups" exist within the subgenus Daphnia (Ctenodaphnia) Dybowski & Grochowski, 1895, containing both described and undescribed species. The Daphnia similis group is among these species groups. The aim of the present paper is to revise the taxonomy of the Daphnia (Ctenodaphnia) similis group in the Old World with both morphological and genetic evidence (based on mitochondrial COI and 12S rRNA genes). We found that there are at least four species in the Old World D. similis species group: D. similis Claus, 1876; D. sinensis Gu, Xu, Li, Dumont et Han, 2013; D. similoides Hudec, 1991 and D. inopinata sp. nov. These four taxa of the similis-group, confused previously with D. similis, have different distributional ranges in the Old World, from extremely wide, spanning several biogegraphic regions (as D. sinensis), to regional endemics (D. similoides) and even species known so far from a single locality (D. inopinata sp. nov.). The Daphnia similis group provides another example in the cladocerans whereby the study of males yields more valuable characters for taxonomy than the study of parthenogenetic females.

Climate change affected ecological community make-up during the Quaternary which was probably both the cause of, and was caused by, evolutionary processes such as species evolution, adaptation and extinction of species and populations.