Martin Zuschin | University of Vienna (original) (raw)

Papers by Martin Zuschin

Palaeogeography, Palaeoclimatology, Palaeoecology, 2016

Predatory drilling traces are routinely used to evaluate temporal patterns in animal behaviour. H... more Predatory drilling traces are routinely used to evaluate temporal patterns in animal behaviour. However, for testing such trends it is important to consider natural and methodological variability that may play a role in shaping drilling patterns. The present study attempts to test this notion by evaluating the drilling patterns of the molluscan fauna in relation to stratigraphy, locality, sieve size (4 mm, 2 mm, 1 mm) and taxonomic affinity at class level. We studied drilling predation using molluscan specimens from three localities (Grignon, La Ferme de l'Orme, Fleury-la-Rivière), representing a variety of elementary depositional sequences (EDS) from the Middle Lutetian strata of the Paris Basin. The overall drilling frequency (DF) averaged over the three localities is 17%; bivalves show a significantly higher overall DF (18%) compared to gastropods (14%) and scaphopods (b0.01%). For all higher taxa and at all localities DF is highest in the medium size class (2-4 mm), which we relate to the dominance of preferred prey species in this category. Despite having similar diversity profiles of molluscan fauna, the three localities show distinct drilling patterns with highest frequencies in Grignon (overall 25%, bivalves 29%, gastropods 20%), followed by Fleury-la-Rivière (overall 18%, bivalves 17%, gastropods 18%) and almost a complete lack of drill holes in La Ferme de l'Orme. This pattern is true for each sieve size of molluscs, bivalves and gastropods. The results are similar for common species found in all three localities. EDS2-3 representing a mesotrophic environment during a regressive phase shows a slightly higher DF compared to oligotrophic EDS4, from the following transgression. Locality emerges as the strongest predictor of DF when evaluated for the relative role of stratigraphy, locality, sieve size and higher taxa. The occurrence of incomplete drill holes is relatively rare and increases with sieve size, implying a possible existence of handling limit of the predatory gastropods. There are very few occurrences of edge drilling. The combined variation documented in this study is comparable in magnitude with many temporal shifts documented previously. Therefore, in order to establish any temporal pattern in drilling behaviour it is vital to evaluate and control for the potential gradient of other natural variabilities in predatory behaviour. Species composition and diversity has been used previously to resolve the debate on climate conditions of the Eocene Paris basin through a comparison to modern analogues. We have used a similar approach by comparing predation patterns with Recent localities of subtropical and temperate regions. The available data from the Eocene Paris basin, from the warm-temperate northern Adriatic Sea and from the subtropical Red Sea show very heterogeneous patterns, depending on the drilling metric considered. Considering the strong patchiness of drilling predation within each of these basins and reported from many other studies, we conclude that a climatic affiliation of the Eocene Paris basin based on drilling metrics is not yet possible.

GSA Annual Meeting in Indianapolis, Indiana, USA - 2018, 2018

Marine Ecology, Jun 7, 2016

This study examined two shallow-water, offshore oil facilities and their surroundings in the Umm ... more This study examined two shallow-water, offshore oil facilities and their surroundings in the Umm Al Dalkh and Zakum oilfields [United Arab Emirates, Persian (Arabian) Gulf]. The focus was on sediment contamination levels and the detection of disturbance based on two representative invertebrate components of the benthos: molluscs and polychaetes. We tested the hypothesis that significant disturbance to the community has occurred, by examining whether distance from the platform or variation in contaminants explains among-site variation in the composition of benthic communities. Moreover, we also tested the hypothesis that organic enrichment because of oil input has modified the feeding guild structure by examining whether the relative abundances of filterfeeders, deposit-feeders and omnivores are correlated with distance from the platform or with contamination by hydrocarbons. The contamination levels and their spatial distribution in the sediments differed significantly between the two fields, as did their mollusc and polychaete communities. The within-field variability, however, was much lower: no clear structuring of contamination values and species composition and abundance was detectable in relation to distance from the oil platform. Contamination levels were low, often below detection levels or international guideline values. Variation in contaminant concentrations did not explain variation in taxonomic composition and abundance. The relative abundance of the above-mentioned feeding guilds did not correlate with either distance from the platform or with contaminant concentrations. These patterns may reflect the long time that has elapsed since drilling (15-20 years), which appears to have allowed contaminants to disperse and degrade and assemblages to recover from the impact, if indeed such a disturbance ever occurred. In contrast to low values of barium and total petroleum hydrocarbons, associated with well drilling, some metals were at their highest concentrations beneath the central platforms. This suggests that productionrelated activities (including platform cleaning and maintenance) are currently a more relevant contamination source.

Marine Pollution Bulletin, Oct 1, 2021

The Eastern Mediterranean Sea hosts more non-indigenous species than any other marine region, yet... more The Eastern Mediterranean Sea hosts more non-indigenous species than any other marine region, yet their impacts on the native biota remain poorly understood. Focusing on mollusks from the Israeli rocky intertidal, we explored the hypothesis that this abiotically harsh habitat supports a limited trait diversity, and thus may promote niche overlap and competition between native and non-indigenous species. Indeed, native and non-indigenous assemblage components often had a highly similar trait composition, caused by functionally similar native (Patella caerulea) and non-indigenous (Cellana rota) limpets. Body size of P. caerulea decreased with increasing C. rota prevalence, but not vice versa, indicating potential asymmetric competition. Although both species have coexisted in Israel for >15 years, a rapid 'replacement' of native limpets by C. rota has been reported for a thermally polluted site, suggesting that competition and regionally rapid climate-related seawater warming might interact to progressively erode native limpet performance along the Israeli coast.

Palaeogeography, Palaeoclimatology, Palaeoecology, Sep 1, 2016

Live-dead (LD) fidelity studies are a fundamental tool for assessing the quality of the paleobiol... more Live-dead (LD) fidelity studies are a fundamental tool for assessing the quality of the paleobiological information preserved in the fossil record. An important feature of death assemblages (DAs) is that they are time-averaged to some degree. Previous studies found that subtidal carbonate environments are characterized by lower timeaveraging in comparison to siliciclastic settings, primarily because of a high rate of shell loss due to bioerosion and dissolution. These factors lead to increased temporal resolution in subtidal carbonate death assemblages (DAs) but more intense bias in species composition due to differential loss of vulnerable shells. A consequence of lower time-averaging is a better match in live-dead (LD) richness. We evaluated LD fidelity of molluscan assemblages from soft sediments in subtropical, carbonate tidal flats along the coast of the United Arab Emirates (Persian (Arabian) Gulf) to test these predictions. A total of 7193 mollusks from six sites were analyzed. We found that DAs are, on average, over five times richer than living assemblages (LAs) at site scale, and nearly five times at habitat scale. We found that early cementation, lateral mixing, intense bioturbation and moderate sedimentation rates can account for large LD differences in richness. Differential intensity in lateral mixing by post-mortem transport inflated alpha, beta, and gamma diversity by 28, 10 and 42%. However, beta diversity is strongly underestimated in DAs when compared to LAs. Evenness was larger in DAs both at site and at habitat scales, but there was only a high mismatch at sites with patchy LAs. Fidelity of feeding guild structure was high for rank abundance, with secondary consumers well represented in DAs. The occurrence of out-of-habitat taxa did not affect fidelity in rank-abundance of feeding guild structure. Our results suggest that timeaveraging in carbonate tidal flats can potentially be higher compared with subtidal carbonate environments.

Proceedings of The Royal Society B: Biological Sciences, Jun 17, 2020

Palaeoecological data are unique historical archives that extend back far beyond the last several... more Palaeoecological data are unique historical archives that extend back far beyond the last several decades of ecological observations. However, the fossil record of continental shelves has been perceived as too coarse (with centennial-millennial resolution) and incomplete to detect processes occurring at yearly or decadal scales relevant to ecology and conservation. Here, we show that the youngest (Anthropocene) fossil record on the northern Adriatic continental shelf provides decadal-scale resolution that accurately documents an abrupt ecological change affecting benthic communities during the twentieth century. The magnitude and the duration of the twentieth century shift in body size of the bivalve Corbula gibba is unprecedented given that regional populations of this species were dominated by small-size classes throughout the Holocene. The shift coincided with compositional changes in benthic assemblages, driven by an increase from approximately 25% to approximately 70% in median per-assemblage abundance of C. gibba. This regime shift increase occurred preferentially at sites that experienced at least one hypoxic event per decade in the twentieth century. Larger size and higher abundance of C. gibba probably reflect ecological release as it coincides with an increase in the frequency of seasonal hypoxia that triggered mass mortality of competitors and predators. Higher frequency of hypoxic events is coupled with a decline in the depth of intense sediment mixing by burrowing benthic organisms from several decimetres to less than 20 cm, significantly improving the stratigraphic resolution of the Anthropocene fossil record and making it possible to detect sub-centennial ecological changes on continental shelves.

EGU General Assembly Conference Abstracts, Apr 1, 2016

EGU General Assembly Conference Abstracts, Apr 1, 2015

Palaeogeography, Palaeoclimatology, Palaeoecology, May 1, 2016

Community studies in paleontological research often rely on identification at taxonomic levels hi... more Community studies in paleontological research often rely on identification at taxonomic levels higher than species (mainly genus or family). Several studies have been conducted on paleo-and modern communities to identify the higher level of taxonomic identification that still depicts ecological patterns: genus-and, to a lesser extent, family-level identification are frequently sufficient. The use of higher taxonomic levels has not yet been explored in the context of studies comparing living and death assemblages (so-called "live-dead agreement studies"), notwithstanding their interest to quantify the fidelity of the fossil record and for environmental assessment. We conducted such exploration in a highly diverse tropical marine setting, targeting shelled molluscs. Our results suggest that the common practice of genus-level identification of paleontological samples allows for a proper reconstruction of the original biological community (e.g., variation in richness, ecological or taxonomic similarity) at the species level because (1) fidelity at the species and genus levels is very similar and (2) genera are sufficient to characterize between-habitat differences in composition and diversity. Live-dead agreement becomes even better at family and higher taxonomic levels for some metrics, but between-habitat differences in composition become weaker above the family level. However, at the genus and family levels, between-habitat differences are equally strong as at the species level. Genus-level identification may provide more robust results when one of the assemblages is dominated by a single species, because differences in abundance can be compensated by co-generic species. Moreover, in death and fossil assemblages, diagnostic characters get lost easily because of taphonomic processes such as abrasion, dissolution, and fragmentation; nonetheless, genus-and family-level identifications can still be reliable because the most conspicuous diagnostic characters which characterize higher taxa are more persistent after the death of the mollusc.

Biological Invasions, Nov 24, 2017

Human disturbance modifies selection regimes, depressing native species fitness and enabling the ... more Human disturbance modifies selection regimes, depressing native species fitness and enabling the establishment of non-indigenous species with suitable traits. A major impediment to test the effect of disturbance on invasion success is the lack of long-term data on the history of invasions. Here, we overcome this problem and reconstruct the effect of disturbance on the invasion of the bivalve Anadara transversa from sediment cores in the Adriatic Sea. We show that (1) the onset of major eutrophication in the 1970s shifted communities towards species tolerating hypoxia, and (2) A. transversa was introduced in the 1970s but failed to reach reproductive size until the late 1990s because of metal contamination, resulting in an establishment and detection lag of *25 years. Subfossil assemblages enabled us to (1) disentangle the distinct stages of invasion, (2) quantify time-lags and (3) finely reconstruct the interaction between environmental factors and the invasion process, showing that while disturbance does promote invasions, a synergism of multiple disturbances can shift selection regimes beyond tolerance limits and induce significant time lags in establishment. The quantification of these time lags enabled us to reject the hypothesis that aquaculture was an initial vector of introduction, making shipping the most probable source.

Biogeosciences Discussions, 2015

We present the first analysis of population structure and cohort distribution in a fossil oyster ... more We present the first analysis of population structure and cohort distribution in a fossil oyster reef based on more than 1121 shells of the giant oyster Crassostrea gryphoides (Schlotheim, 1813). Data derive from Terrestrial Laser Scanning of a Lower Miocene shell bed covering 459 m 2. Within two transects, individual shells were manually outlined on a digital surface model and cross-checked based on high-resolution orthophotos, resulting in accurate information on center line length and area of exposed shell surface. A growth model was calculated, revealing this species as the fastest growing and largest Crassostrea known so far. Non-normal distribution of size, area and age data hints at the presence of at least four distinct recruitment cohorts. The rapid decline of frequency amplitudes with age is interpreted to be a function of mortality and shell loss. The calculated shell half-lives range around few years, indicating that oyster reefs were geologically short-lived structures, which could have been fully degraded on a decadal scale. Crassostrea gryphoides reefs were widespread and common along the Miocene circum-Tethyan coasts. Given its enormous growth performance of ∼ 150 g carbonate per year this species has been an important carbonate producer in estuarine settings. Yet, the rapid shell loss impeded the formation of stable structures comparable to coral reefs.

Marine Ecology Progress Series

Biogeographical patterns are increasingly modified by the human-driven translocation of species, ... more Biogeographical patterns are increasingly modified by the human-driven translocation of species, a process that accelerated several centuries ago. Observational datasets, however, rarely range back more than a few decades, implying that a large part of invasion histories went unobserved. Small-sized organisms, like benthic foraminifera, are more likely to have been reported only recently due to their lower detectability compared to larger-sized organisms. Recently detected native species of tropical affinity may have thus been mistaken for non-indigenous species due to the lack of evidence of their occurrence in pre-invasion records. To uncover the unobserved past of the Lessepsian invasion—the entrance of tropical species into the Mediterranean through the Suez Canal—we collected sediment cores on the southern Israeli shelf. We deployed state-of-the-art radiocarbon techniques to date 7 individual foraminiferal tests belonging to 5 alleged non-indigenous species and show that they a...

Invertebrate lineages tend to originate and become extinct at a higher rate in onshore than in of... more Invertebrate lineages tend to originate and become extinct at a higher rate in onshore than in offshore habitats over long temporal durations (more than 10 Myr), but it remains unclear whether this pattern scales down to durations of stages (less than 5 Myr) or even sequences (less than 0.5 Myr). We assess whether onshore–offshore gradients in long-term turnover between the tropical Eocene and the warm-temperate Plio-Pleistocene can be extrapolated from gradients in short-term turnover, using abundances of molluscan species from bulk samples in the northeast Atlantic Province. We find that temporal turnover of metacommunities does not significantly decline with depth over short durations (less than 5 Myr), but significantly declines with depth between the Eocene and Plio-Pleistocene (approx. 50 Myr). This decline is determined by a higher onshore extinction of Eocene genera and families, by a higher onshore variability in abundances of genera and families, and by an onshore expansion of genera and families that were frequent offshore in the Eocene. Onshore–offshore decline in turnover thus emerges only over long temporal durations. We suggest that this emergence is triggered by abrupt and spatially extensive climatic or oceanographic perturbations that occurred between the Eocene and Plio-Pleistocene. Plio-Pleistocene metacommunities show a high proportion of bathymetric generalists, in contrast to Eocene metacommunities. Accordingly, the net cooling and weaker thermal gradients may have allowed offshore specialists to expand into onshore habitats and maintain their presence in offshore habitats

PALAIOS, 2009

A bathymetric transect ranging from coral habitats down to a 1500-mdeep basin in the Red Sea and ... more A bathymetric transect ranging from coral habitats down to a 1500-mdeep basin in the Red Sea and Gulf of Aden allows us to test the sensitivity of taphofacies to depth and sediment grain size in a tropical to subtropical carbonate basin, to partition variation in brachiopod preservation into extrinsic (environmental) and intrinsic (shell-specific) components, and to quantify residual variation that remains unexplained by such components. Factoring out environmental effects, thin-shelled, organic-poor rhynchonellids are more affected by fragmentation and finescale surface alteration and degrade rapidly compared to the more frequently bioeroded, organic-rich terebratulids. The negative role of shell organic content is overridden by shell thickness, and preservation rates of organic-rich brachiopods are enhanced by syndepositional cement precipitation. Environmental trends in preservation are confounded by shell-specific factors that account for 16% of variation in preservation: the amounts of multivariate variation explained by environment increase from 29% using combined brachiopod preservation to 46% using terebratulid preservation. Environmental sensitivity of taphofacies is driven by present-day variation in environment but also by past Pleistocene conditions. First, reduction in fragmentation, encrustation, and bioerosion is consistent with a decrease in light penetration and primary productivity. Second, brachiopods are coated with aragonite cement in basinal sites with lithified oozes and microbial carbonates that originated during the last glacial maximum when syndepositional aragonite cementation was favored by high temperature and salinity, and thus can be affected by millennial-scale time averaging. Skeletal preservation rates are thus not in steady state over the duration of time averaging, and the bathymetric reduction in alteration is partly related to past conditions amenable to cement precipitation.

Drilling predation is among the most studied biotic interactions in the fossil record, and its ov... more Drilling predation is among the most studied biotic interactions in the fossil record, and its overall patterns are well established on Cenozoic molluscs from North America. Few studies have examined such predation in Europe. This study aims to evaluate molluscan drilling intensities from the Burdigalian, Langhian and Serravallian of the Central Paratethys. Using drill frequency (DF) and prey effectiveness (PE),

Body size data for Brachidontes pharaonis and Pinctada imbricata radiata from multiple sites acro... more Body size data for Brachidontes pharaonis and Pinctada imbricata radiata from multiple sites across their native (Red Sea and NW Indian Ocean) and invaded range (Mediterranean Sea and Suez Canal).

List of bivalve species reported from shelf depths in the Mediterranean Sea and the Red Sea, thei... more List of bivalve species reported from shelf depths in the Mediterranean Sea and the Red Sea, their alien status in the Mediterranean, body size, and taxonomic and functional affiliation.