Assessing spider diversity in grasslands – does pitfall trap color matter? has been accepted in Journal of Arachnology.
Authors Möller M & Buchholz S
We analyzed effects of pitfall trap color (white, yellow, green, brown) on spider catches and found differences in alpha-diversity and one biological trait, namely hunting type. Attractiveness of different trap colors may arise due to differences in biological preconditions, albedo and microclimate which in turn can affect diversity and community structure of spiders. Trap color has a significant impact on spider catches and should be considered when planning surveys.
Conference talk in Greifswald
Last weekend the conference of the German Arachnological Society took place in Greifswald. I gave a talk on trait-based approaches and functional diversity in arachnology and presented progresses and perspectives within this research topic (see slides). Trait-environmental relationships and functional diversity are very important components within biodiversity research and several studies have successfully applied these concepts to spiders. Unfortunately, a consensus how to select appropriate morpho-physiological, phenological and ecological traits and to define trait categories is missing yet. Therefore, my talk intended to encourage the development of a standardised and expert-based open-access trait database for spiders. It was great to have some fruitful discussions afterwards. We agreed on organising an expert workshop soon to work out a first proposal for a meaningful trait selection.
Urban birds of prey
Several raptor species become more and more urban dwellers and they thrive very well in many different urban habitats now. In Berlin, four species are very common – even in heavily urbanised areas. While the common buzzard (Buteo buteo) mostly inhabits parks and urban woodlands, aeries of the peregrine falcon (Falco peregrinus) and the common kestrel (Falco tinnunculus) can be found in higher buildings all over the city. The latter can be regularly seen at the Tempelhofer Feld (see photo) and a good place to observe the peregrine falcon is the Alexanderplatz and the television tower which is used as raised hide, even during the night.
In the last years, we conducted research on the northern goshawk (Accipiter gentilis). Interestingly, this species spreads more and more into the heavily urbanised areas and while it was breeding in urban parks and large gardens at the beginning, aeries can be found in backyards in isolated tree by now. Sometimes northern goshawks are even hunting in busy roads like the Schlesische Straße in Kreuzberg. Watch out for more findings …
Biodiversity functions of urban cemeteries: evidence from one of the largest Jewish cemeteries in Europe has been accepted for publication in Urban Forestry & Urban Greening.
Authors Kowarik I, Buchholz S, von der Lippe M & Seitz B
Abstract As the world becomes more urbanized, urban cemeteries may become increasingly valuable for biodiversity conservation as cemeteries are ubiquitous elements of the green infrastructure in cities worldwide. By implementing a multi-taxon approach at different spatial extents, we analyzed habitat functions of a large urban cemetery in Berlin (Weißensee Jewish Cemetery) and explored related environmental variables. This cemetery is an outstanding cultural heritage site but it also stands for old urban cemeteries that have progressed to urban woodland, an ecosystem type that exists in many regional and religious contexts. The cemetery provided a habitat for 604 species; species of conservation concern comprised 1.6–100% of total species among different groups of taxa (in decreasing order: bats, birds, lichens, bryophytes, carabids, vascular plants, spiders). Species richness and species composition at the plot level were significantly related to differences in management intensity and resulting vegetation structures but differed among taxonomic groups. In vascular plants, carabids and spiders, the species composition varied significantly with habitat age, and there was a set of characteristic species for different age classes in each species group. Our results thus support the use of differentiated management approaches to maintain habitat heterogeneity by allowing wilderness development in some parts of a cemetery while keeping others more open. Since these aims can be combined with efforts to preserve outstanding grave architectures and allow access to visitors, our study indicates ways of reconciling conflicting aims of heritage preservation and biodiversity conservation, a promising perspective for biodiversity conservation in culturally shaped urban landscapes. We conclude that cemeteries provide important cultural ecosystem services within the urban green infrastructure.
Insects and spiders of Galápagos
Together with my colleagues from the invertebrate lab of the Charles Darwin Research Station I recently finished the identifications of the spider, beetle and bug samples from the Los Gemelos project. We found a number of very interesting endemic species such as the spiders Darwinneon crypticus, Galaporella thaleri or Olios galapagoensis as well as endemic beetles such as Anchonus galapagoensis, Ataenius aequatorialis or Mordellistena galapagoensis. It was a great experience for me to see all this new species – and of course to work with the awesome team. Many thanks! Back in Berlin again, I am going to run the statistical analyses – look out for coming publications. If you are already interested in some basic results from the Los Gemelos project please make a note of the following paper which will published in the Galápagos Report soon:
Restoration of the blackberry-invaded Scalesia forest: impacts on the vegetation, invertebrates and birds (by Jäger H, Cimadom A, Buchholz S, Tebbich S, Rodriguez J, Barrera D, Breuer M, Walentowitz A, Carrión A, Sevilla C & Causton C)
Sailing Isabela island with my binoculars
Last weekend I went to Isabela island and I am happy to add two more species to my birding-list: the Black-necked Stilt (Himantopus mexicanus, r) and the Galápagos Petrel (Pterodroma galapagensis, e). It was really amazing to snorkel with Galápagos penguins and dozens of Blue-footed Boobies …
On the move with my binoculars
Galápagos is a great place for birdwatching and thus during my field trips and boat cruises I spent some time with my binoculars to glass the islands and the ocean. Up to now, I saw 41 species – see my species-list. There are only about 60 resident species and 13 of these are the finches. The relative paucity of species is in reality one of the beauties of Galápagos birds. The finches and mockingbirds are excellent examples of adaptive radiation and I am now very happy to have some photos for my animal ecology lecture. The number of resident species is growing. Two species have been introduced: pigeons, which have now been eradicated, and the Smooth-billed Ani. The Cattle Egret has arrived unaided. In addition to the resident species, there are numerous regular visitors, mainly migratory waders from North America. Here are some pictures I took during my trips … Find more in the photo gallery!
Bird ringing at Los Gemelos
Together with Arno Cimadom, his team from the University of Vienna and researchers of the Charles Darwin Research Station I spent gorgeous morning hours in the highlands of Santa Cruz. We captured darwin finches (e.g. warbler and tree finches as well as the woodpecker finch) using mist nets and ringed them. The field work was part of the Los Gemelos research project which among others focuses on how control of the invasive blackberry affects darwin finches in the Scalesia forests. I usually work with invertebrates – not only in this project – and thus I was glad to do some ornithological work for a change.
Biological richness of a large urban cemetery in Berlin. Results of a multi-taxon approach has been published in the Biodiversity Data Journal.
Urban green spaces can harbor a considerable species richness of plants and animals. A few studies on single species groups indicate important habitat functions of cemeteries, but this land use type is clearly understudied compared to parks. Such data are important as they (i) illustrate habitat functions of a specific, but ubiquitous urban land-use type and (ii)
may serve as a basis for management approaches. We sampled different groups of plants and animals in the Weißensee Jewish Cemetery in Berlin (WJC) which is one of the largest Jewish cemeteries in Europe. With a total of 608 species of plants and animals, this first multi-taxon survey revealed a considerable biological richness in the WJC. In all, 363 wild-growing vascular plant, 72 lichen and 26 bryophyte taxa were recorded. The sampling also yielded 34 bird and 5 bat species as well as 39 ground beetle, 5 harvestman and 64 spider species. Some species are new records for Berlin.