Croatian Natural History Museum’s scientific contributions

The striped dolphin (Stenella coeruleoalba) is not a common cetacean species in the northern Adriatic Sea. Its presence is generally related to deeper offshore areas beyond the continental shelf. Despite this fact, the analysis of data collected over the past 5 years indicates unusual site fidelity of a single individual in the relatively shallow Vinodol Channel of the northern Croatian Adriatic Sea. Summarizing the available data on its recent occurrence, this paper contributes to the current limited knowledge on striped dolphin presence and associations not only in this region.

In this paper we examine the distribution of amphibians and reptiles over the islands of the newly founded Lastovo Archipelago Nature Park (Lastovsko otočje), Croatia. On several field trips between 1996 and 2008, we encountered five species of lizards (Podarcis sicula, P. melisellensis, Dalmatolacerta oxycephala, Hemidactylus turcicus and Pseudopus apodus), one species of snake (Dolichophis caspius), one species of sea turtle (Caretta caretta) and one species of toad (Bufo viridis). We confirm literature data on the presence of some of these species on different islands of the archipelago, and add distributional records for several other islands and islets. Logistic regression analyses show that the variables predicting presence/absence from different islands vary among species. Within species, populations from different islands noticeably vary in body size and shape, scalation, dorsal and ventral coloration, behaviour and density. This observation adds to the value of the study area as a »natural laboratory« for future research into the ecology and evolution of island populations. Although most species seem to be doing well presently, we list a number of possible hazards and concerns.

Presented data brings data on ichthyofauna of four localities on Kupa, Orljava, Lonja and Glina Rivers of the Sava River basin (Danube drainage) in central Croatia. We have recorded one lamprey and 30 fish species, three of them not native for European fauna and eight threatened in Croatian fauna. We have found three species from the Cobitidae family, C. elongatoides, Misgurnus fossilis and Sabanajewia balcanica. Ecological characteristics of C. elongatoides distribution are discussed.

Results of non invasive virtual imaging of normal and altered wild boar tusks are presented. Pathologically altered tusk structure is presented for two pairs of mandibular canines that experienced different traumatic impacts and in one lower mandible with a complete loss of the right lower canine. Wild boar tusks represent a valuable material for dental pathologists due to their characteristic position and consequent predisposition to injury, their enormous reparative potential and the fact that they are collected and kept as trophies over extended periods of time. However, their value as trophy often limits the possibility of analysis of internal structural changes by destructive methods. In this situation, the use of non invasive methods can provide insights into the nature of pathological and reparation processes related to traumatic impacts on wild boar tusks.

We present the first list of butterflies of Blidinje Nature Park, comprising 91 estimated species. The estimated number of species constitutes about 90% of the potential Rhopalocera fauna in this area.

In order to build up the data infrastructure on the chorology of Croatian vascular flora, the present data on the distribution of taxa from the class Lycopsida were collected from literature and herbarium sources. For 8 taxa of Croatian flora 325 localities were found, and 108 localities of herbarium specimens and 172 localities cited in the literature were geocoded. The distribution was represented with a list of localities and maps using a Central European grid for floristic mapping. The amounts of data available for given MTB squares indicated that the mountain macro-region (especially the Gorski kotar and Lika meso-region) was better investigated.

The model of spatial distribution of major forest types in Croatia was developed as a function of macroclimatic variables (monthly mean temperature, monthly precipitation, monthly mean global solar irradiation and monthly potential evapotranspiration) and variables derived from digital elevation model (terrain aspect and slope). Neural networks were used as modelling tool. The model was developed within the frame of a raster geographic information system with a spatial resolution of 300 × 300 m, and it was based on a forest vegetation map (in scale of 1 : 500000) and interpolation macroclimatic models. The agreement between modelled and mapped forest types was very good, which suggests a strong correlation between macroclimate and the main forest types in Croatia and high model reliability. The model was applied to the entire area of Croatia, aiming at the construction of the potential spatial distribution of major forest types. The model could be useful for reforestation planning and for prediction of vegetation succession under assumed climatic changes.

Mycobioindication research was undertaken in the Križ stream catchment area, so as to be able to evaluate current forest health. The forest cover within the area mainly consists of acidophilous fir forest. This study was a part of an Environmental Impact Assessment for a planned drinking water reservoir. The study area belongs to the Gorski kotar region (Croatia) which is subject to strong influence by air pollution from a nearby industrial region (Rijeka bay) and the remote transport of pollutants from heavily industrialised northern Italy. The decline of European silver fir forests in the area has been well documented in previous studies by various authors. For the needs of this research, spatial model of the hypothetical lead load distribution in the soil was extrapolated from a model developed for nearby Risnjak National Park. Plot design and spatial location were determined on the basis of this model. The research presented develops a rapid mycobioindication method, which yields results in line with those presented in the literature. Standardised late autumn fructifying ectomycorrhizal macromycete species with clear mycobioindicative values have been selected and analysed for species diversity and sporocarp productivity. This was done on five 2500 m2 plots distributed in such a way as to cover the whole range of the modelled hypothetical lead load levels. The observed mycobioindication showed a high correlation with the hypothetical lead load and fir defoliation. The spatial distribution of forest health proved to be highly mosaic, mainly as a result of the differing exposure of the spatially variable terrain to air pollution. The quality of the water supply from the future drinking water reservoir is highly dependent on the health of the forests within the catchment area. The method described enables water resource managers to undertake in and on-time remediation measures to protect catchment forest cover.

During 1998, research was done into the flora of and certain ecological factors (temperature and relative humidity) in the entrance parts of three caves on the island of Rab. The caves lie in different vegetation zones and at different altitudes. In all, 32 kinds of plant were recorded: 29 spermatophytes and 3 pteridophytes. In comparison with research carried out in two of the caves at the beginning of the century, a change had occurred in the floristic composition. Particularly noteworthy is the reduction in the number of fern species in the interior of the cave.

By the side of the three already known separate populations of relic stygobiont bivalves of the genus Congeria in the Dinaric karst (Bela Krajina /Slovenia/, western Bosnia /Bosnia and Herzegovina/ and Dalmatia-Herzegovina /Croatia – Bosnia and Herzegovina/) a new population has been found in the underground area of North Velebit, in the drain part of the Lika River, Croatia. After the discovery of part of a shell on the bottom of Lukina Jama pit (–1392 m deep), thousands of specimens of Congeria have been found in Markov Ponor, all the way through more than 1700 m of underground tunnels. As well as a list of associated fauna, a description is provided of some of the ecological factors of the biotope whose temperature reaches a maximum of +6 °C, the lowest temperature in the habitats known.