Daniela Silvia Pace

Sapienza University of Rome | la sapienza · Department of Environmental Biology

In the last decades, interest in species distribution models (SDMs) has grown greatly. The descriptive and predictive power of correlative SDMs is highly valued to meet the high demand for filling gaps in the spatial ecology of wide-ranging and elusive species, such as cetaceans and sea turtles, living in habitats that are technically challenging t...

Sperm whale trumpets are sounds only occasionally documented, with a well recognisable and stereotyped acoustic arrangement. This study investigated the acoustic features of the trumpets and the context in which these sounds were recorded, using acoustic data collected over 22 years, in the Pelagos Sanctuary area (North-Western Mediterranean Sea)....

Periodic assessments of population status and trends to detect natural influences and human effects on coastal dolphin are often limited by lack of baseline information. Here, we investigated for the first time the site-fidelity patterns and estimated the population size of bottlenose dolphins (Tursiops truncatus) at the Tiber River estuary (centra...

Sociality and ecological drivers that can influence individual association patterns are infrequently considered in wildlife management, although they are essential aspects affecting animals’ responses to both human-related pressures and conservation strategies. In common bottlenose dolphins (Tursiops truncatus), sex-specific social dynamics and int...

We report first-time evidence of barrier feeding techniques in the population of common bottlenose dolphin (Tursiops truncatus) at the estuary of the Tiber River (Rome, Italy), used to prey on the flathead grey mullet (Mugil cephalus). We describe an event that occurred in summer 2023, consisting of dolphins forcing schools of mullets against diffe...

The analysis of skin marks and lesions is used for many cetacean species to assess the general health status of the populations, based on evidence of interaction between conspecifics and with human activities. This study applies mark analysis to characterise common bottlenose dolphin ( Tursiops truncatus ) skin marks and lesions, and their evolutio...

The common bottlenose dolphin (BD) is a key apex predator in the marine environment, inhabiting a high diversity of habitats, from highly-urbanised coastal and estuarine settings to more pelagic ones. BDs accumulate on the skin signs of the interaction with the surroundings (e.g., presence of parasites, hints of changes in environmental parameters)...

Malta’s eastern and southern coasts are affected by aquaculture activities and fishing with FAD (Fishing Aggregating Devices). Both are known to have influences on the environment, habitats and biodiversity, by altering species richness and abundance, and thus having the potential to impact higher trophic level predators, including bottlenose dolph...

Accurately capturing information on the spatial ecology of cetaceans is challenging due to their mobility and the difficulty of surveying underwater habitats. However, addressing these challenges is imperative for informing conservation strategies for species vital to marine biodiversity and facing increasing threats from human-induced pressures. C...

The assessment of female reproductive parameters is pivotal to determine the viability of bottlenose dolphin (Tursiops truncatus, BD) populations, especially those living in highly urbanized coastal areas. This study is focused on the analysis of these parameters in the BD population living in the Roman seas at the Tiber River estuary (central Tyrr...

The common bottlenose dolphin (Tursiops truncatus, BD) can produce distinctive sequences composed of multi-unit rhythmic signals at low frequency and short duration, known as the Bray-Call series (BC). BCs have been mainly recorded during feeding activities, but little is known about their possible communicative function in social contexts. The BD...

This work aims to show how prior knowledge about the structure of a heterogeneous animal population can be leveraged to improve the abundance estimation from capture-recapture survey data. We combine the Open Jolly-Seber model with finite mixtures and propose a parsimonious specification tailored to the residency patterns of the common bottlenose d...

During foraging dives, sperm whales produce series of regular clicks interspersed with sequences of rapid–click buzzes called ‘creaks’, often followed by a few seconds of silence (“creak-pause” event), thought to be indicative of feeding attempts/success. Here, a total of 406 creaks in 163 recordings, collected between 2017 and 2021, were examined...

The common bottlenose dolphin (Tursiops truncatus, BD) is recognized as a species with high vocal plasticity, able to adjust the acoustic parameters of the emitted signals based on different environmental, social, and behavioral settings. The degree of the variations related to the context of emission and the weight of each influencing factor is st...

The long-finned pilot whale (Globicephala melas) is a highly social species with an extremely complex vocal repertoire. Very little is known about the repertoire of the Inner Mediterranean sub-populations (occurring from the eastern Alborán Sea to Ligurian Sea). Here, the acoustic features of 919 pilot whales’ whistles (i.e., tonal, frequency-modul...

In this work, the goal is to estimate the abundance of an animal population using data coming from capture-recapture surveys. We leverage the prior knowledge about the population's structure to specify a parsimonious finite mixture model tailored to its behavioral pattern. Inference is carried out under the Bayesian framework, where we discuss suit...

Over the last century, P. oceanica meadows have undergone significant regression along Mediterranean coasts due to anthropogenic disturbances. Using an integrated approach based on historical aerial photography interpretation in GIS environment and Bayesian modelling, we mapped the upper limits of a P. oceanica meadow and identified the most influe...

Certificate of top downloaded article in AquCons: Marine&Freshwater Ecosystems

We investigated the presence and diversity of cetaceans in the Mediterranean Sea, analysing the data collected by 32 different research units, over a period of 15 years (2004–2018), and shared on the common web-GIS platform named Intercet. We used the encounter rate, the species prevalence, and the Shannon diversity index as parameters for data ana...

Assessing the distribution of marine apex–predators is pivotal to understanding community interactions and defining management goals. However, several challenges arise in both estimates and predictions considering the distinctive and mutable biological/ecological requirements of these species and the influence of human activities. Thus, efforts to...

One of the most studied aspects of animal communication is the acoustic repertoire difference between populations of the same species. While numerous studies have investigated the variability of bottlenose dolphin whistles between populations, very few studies have focused on the signature whistles alone and the factors underlying differentiation o...

Acoustic sequences are commonly observed in many animal taxa. The vast vocal repertoire of common bottlenose dolphins (Tursiops truncatus) also includes sequences of multi-unit rhythmic signals called bray-call which are still poorly documented, both functionally and geographically. This study aimed to (1) describe, classify, and characterize serie...

Epimeletic behavior toward dead calves has been frequently reported in cetaceans, mostly with females (presumed mothers) showing supportive behaviors such as carrying, lifting, or sinking, often assisted by “escort” individuals. However, information on acoustic production in such contexts is scarce. This report describes two observations of epimele...

Seagrasses rank among the most productive yet highly threatened ecosystems on Earth. Loss of seagrass habitat because of anthropogenic disturbances and evidence of their limited resilience have provided the impetus for investigating and monitoring habitat restoration through transplantation programmes. Although Structure from Motion (SfM) photogram...

These datasets derived from our mapping protocol are presented as a research article in the Journal of Environmental Management [1]. In particular, by using a Structure from Motion photogrammetric workflow we produced high spatial resolution 2D raster maps and 3D outputs such as dense points clouds and textured meshes of an underwater seagrass rest...

Presence‐only data are typical occurrence information used in species distribution modelling. Data may be originated from different sources, and their integration is a challenging exercise in spatial ecology as detection biases are rarely fully considered. We propose a new protocol for presence‐only data fusion, where information sources include so...

Coralligenous reefs are characterized by large bathymetric and spatial distribution, as well as heterogeneity; in shallow environments, they develop mainly on vertical and sub-vertical rocky walls. Mainly diver-based techniques are carried out to gain detailed information on such habitats. Here, we propose a non-destructive and multi-purpose photo...

1. Dolphins interact with many types of fishing gear, causing damage to fishing activities and in some cases facing harm and becoming entangled as bycatch. 2. In this study, the behaviour of bottlenose dolphins during their interaction with set nets, equipped with and without interactive pingers, was investigated. Acoustic monitoring of the nets w...

The assessment of effective and affordable restoration interventions is pivotal to developing new tools to mitigate habitat loss and enhance natural recovery. Gorgonians create important three-dimensional habitats in the Mediterranean Sea providing several ecosystem services associated with coralligenous reefs. Transplantations of the octocorals Eu...

The Conservation and Research of the endangered Mediterranean Common dolphin, Delphinus delphis is presented in the special issue published by Aquatic Conservation: Marine and Freshwater Ecosystems - Vol 31 Supplement 1. Guest Editors : DS Pace, B Mussi, JG Vella & A Vella. Thanks are due to the three NGOs (BICREF, OCEANOMARE DELPHIS, OCEAN CARE) t...

Presence-only data are a typical occurrence in species distribution modeling. They include the presence locations and no information on the absence. Their modeling usually does not account for detection biases. In this work, we aim to merge three different sources of information to model the presence of marine mammals. The approach is fully general...

Preservation of endangered species is now recognized as a relevant component of regional and global conservation actions achieved through the maintenance of the remaining populations in a favourable conservation status. The Mediterranean common dolphin (Delphinus delphis) is listed as an Endangered subpopulation in the International Union for Conse...

This paper summarizes facts and outcomes of the Mediterranean short‐beaked common dolphin (Delphinus delphis) workshop.

The evaluation of acoustic temporal rhythms in wide-ranging cetaceans can reveal patterns in animal spatial presence and the occurrence of periodical phenomena. Here, we aimed at assessing the temporal patterns of dolphin's acoustic presence in a shallow-water area in the Sicily Strait (Mediterranean Sea). Whistles were collected continuously for 1...

We report here for the first time the effectiveness of Reteporella bryozoan genus in the early stage of coralligenous reefs recolonization through the analysis of the settlement and the population size structure over a two-years period at two impacted and two control sites. Results highlighted how Reteporella spp. colonies strongly recolonized, fro...

Species distribution models (SDMs) provide a useful analytical framework to study the environmental and anthropogenic factors that influence species distribution patterns, returning information that can help to define their geographical ranges and clarify which areas constitute important/sensitive habitat for their survival. For cetaceans, it has b...

Underwater airgun impulses can generate both acute effects, such as temporary/permanent threshold shift in marine mammals hearing, and behavioral reactions. Dolphins are able to adjust their communication signals in relation to fluctuating noise from natural or anthropogenic sources; however, little is known about the variation of communication sig...

1. The short‐beaked common dolphin is a highly vocal species, with a wide distribution in all oceans, including the Mediterranean and the Black Seas. In the Mediterranean Sea, the short‐beaked common dolphin inhabits both pelagic and neritic waters. 2. Osteological collections and the literature show that short‐beaked common dolphins were widesprea...

This study presents data on a local population of short‐beaked common dolphin monitored in the waters off Ischia Island (Gulf of Naples, Italy) over a 16‐year period (2000‐2015). We examine dolphin occurrence and distribution and perform photoidentification analysis. The data presented support the hypothesis that the waters around Ischia Island rep...

When implementing conservation strategies involving passive acoustic monitoring, an accurate description of signal properties is crucial, especially when studying threatened and elusive vocalizing species. Misrepresentation of detected sounds can result in information loss or misclassification of species, thus compromising the management process. D...

1. Sources of data other than those derived from conventional research protocols may contribute valuable information to fill gaps in knowledge about cetacean occurrences and diversity in a given area and help address conservation issues. 2. The performance of a method to examine cetacean communities based on presence records systematically derived...

The identification of significant habitats for highly mobile marine vertebrates is essential for their conservation. Evidence is often difficult to obtain for deep‐diving species such as sperm whales (Physeter macrocephalus), where standard visual survey methods are not sufficient to detect the species. Sperm whales rely on sound for most of their...

The short-beaked common dolphin (Delphinus delphis) is a cosmopolitan cetacean species and relatively little is known on its behaviour and ecology worldwide. In the Mediterranean Sea, the species is listed as ‘endangered’ in the IUCN Red List of Threatened Animals in 2003, based on criterion A2, which refers to a 50% decline in abundance over the l...

SOMMARIO Lo studio dell'impatto dei survey sismici in mare sui mammiferi marini è ancora frammentario e incompleto, mancando un'osservazione degli effetti a lungo termine sulle popolazioni. Nel 2015 l'Italia ha introdotto l'obbligo di condurre survey di studio acustico e visivo sui mammiferi marini presenti nell'area di prospezione almeno per 60 gi...

CONISMA, CNR and CIRCE, involved Italian research units (RUs) working on cetaceans to join a National Network answering the Marine Strategy Framework Directive (MSFD) requirements by sharing monitoring data. Data obtained during the 2016 monitoring campaigns by 13 RUs are presented here.

Concern is growing that marine fauna can be affected by noise such as naval sonar, pile driving or geophysical surveys, among others. Literature reports a variety of animal reactions to human noise (from apparently null or negligible to strong). However, conclusive results on its effects on marine mammals at individual and population level are stil...

The main goal of this research was to contribute to the overall knowledge of the sperm whales’ (Physeter macrocephalus) ecology, sociality, and behavior in the Mediterranean Sea. The combined use of visual and acoustic methods allows me to: 1) give a detailed outline of the encounters around Ischia Island (Tyrrhenian Sea, Italy) over 2004-2015 pe...

Oceanomare Delphis Onlus (Italy), BICREF (Malta) and OceanCare (Switzerland), jointly organized the 1st International Workshop on short‐beaked common dolphin (Delphinus delphis, Linneaus 1758), which took place in Ischia, between the 13th and the 15th of April, in order to assess the status of the Mediterranean population, understand the major thre...

Risso’s dolphins are known for the persistency of their natural markings, possibly due to the loss of pigment during the healing process of skin wounds. Nonetheless, the actual longevity and reliability of each mark type has never been assessed. In this paper, we used photographs to investigate the etiology of skin marks in the species, analyze the...

An unusual observation of a hagfish (Myxine glutinosa) anchored to a living bottlenose dolphin (Tursiops truncatus) was documented in an encounter with a group of about 80 dolphins during an ongoing long-term research program on cetaceans in the central Mediterranean Sea, Italy. The body of the hagfish was observed extruding from the blowhole of th...

This review provides an overview of the Mediterranean diversity and conservation status of cetaceans, and the value associated with their conservation and non-consumptive use. The Mediterranean Sea is one of the world's diversity hotspots; its biodiversity is increasingly under threat in the whole region and key species as cetaceans are under chall...

Pooled data on the endangered short-beaked common dolphin Delphinus delphis collected in the central Mediterranean Sea over 2000-2014 period by different research groups in Italy were analysed. A total of 266 encounters with 4675 common dolphins was attained. The species was mainly recorded in the central and southern Tyrrhenian Sea (around Ischia...

The sperm whale ( Physeter macrocephalus ) is one of the eight species of cetaceans routinely encountered in the Mediterranean Sea; however, information on the social organization of sperm whales living in the basin remains scarce. The social behaviour of sperm whales within female units, and groups of males are reported, made over an 11‐year perio...

Boat surveys aimed at studying sperm whales in the Tyrrhenian Sea were conducted between 2002 and 2011. During 768 daily surveys, a total effort of 32 602 km was achieved within an area of 8800 km ² resulting in 92 encounters with 229 sperm whale individuals. Average encounter rates of sperm whales was 0.5 groups per 100 km ² , with a higher concen...

1. The Mediterranean sperm whale sub-population is considered ‘Endangered’ by both ACCOBAMS and the IUCN. Conservation policies require protected species populations to be monitored, but the distribution and movements of sperm whales across the Mediterranean Sea are still poorly understood. 2. To provide insight into sperm whale movements, the phot...

The sperm whale is one of only two great whales regularly encountered in the Mediterranean Sea. It was once considered to be quite abundant in some parts of the Mediterranean, but large herds are not reported nowadays and several lines of evidence support the hypothesis that the population is depleted. While no estimate of population size exists fo...

Common bottlenose dolphins, Tursiops truncatus, were surveyed in offshore gas fields off Ravenna, Italy, between Spring and Autumn, 2001–2005. These visual surveys provide the first density estimates of bottlenose dolphins in the Northwestern Adriatic Sea south of the Po River. Since no study has examined the distribution of bottlenose dolphins relat...

This paper represents the first quantitative assessment of the distribution and abundance of bottlenose dolphins (Tursiops truncatus) inhabiting the waters around Lampedusa Island, Italy. Eleven years of photo-identification data, collected from 1996 to 2006 by three different research groups, were brought together, reviewed and analysed to fulfil...

Anthropogenic food patches in the marine environment, such as aquaculture farms and active trawlers, may impact on the behavior of marine mammals through modification of habitats, changes in predation pressure, or alterations in food distribution, availability, and predictability, affecting related social interactions and population demographics. T...

There are numerous difficulties encountered in the diffusion of palliative care (PC) in developed countries. A correct and widespread awareness of PC among the general public represents an important factor for its enhanced diffusion and use. The aim of this study is to verify the level of awareness of PC among Italians and their perception of the n...

The first record of killer whale (Orcinus orca) pre-dation on false killer whales (Pseudorca crassi-dens) is reported here. On 25 March 2010, a group of 50 to 60 false killer whales, including approxi-mately 15 calves and accompanied by three to five bottlenose dolphins (Tursiops sp.), were sighted in the Bay of Islands, New Zealand. Within 30 min,...

INTRODUCTION Bottlenose dolphins, Tursiops truncatus, have a global distribution, with the exception of polar waters; in the Mediterranean Sea the species has been studied only in relatively small portions of the basin, wide areas remain largely unexplored and most of the research to date has been conducted in northern portions of the basin, mostly...

Geospatial analysis and GIS are common techniques used in ecological studies to design predictive models. Here we develop a specific model to the study of cetacean species applying various open source tools (Grass and Q-GIS, Geo Server, R, Postgresql with Postgis) to handle behavioural, acoustical, photo-identification, and survey data collected ov...

INTRODUCTION Since 1995, a behavioural research program on pregnancy and mother-calf relationship in bottlenose dolphin has been conducted in the Rimini Delphinarium, Italy. Given that detailed quantitative behavioural aspects of gestation and parturition in dolphins have been rarely described in reproductive reports, the objective of this study wa...

Driftnet fishing is notorious for being the major source of fatal entanglement of cetaceans and for its devastating impact on some pelagic species of the Mediterranean fauna. Of all the large cetaceans, the sperm whale (Physeter macrocephalus) is most affected by this fishing technique. On 9 August 2004, a group of five sperm whales, two adult fema...