First, we would like to thank both reviewers for acknowledging the novelty of our study, for showing interest and enthusiasm in our work, and for raising important questions and comments about our findings.

While we reserve the opportunity to correct additional grammatical errors and to respond more specifically to the questions highlighted by the reviewers in a subsequent interaction, we would like to address the most important concerns raised in their reports:

1. The influence of water masses (mCDW, HSSW, and/or brine production) on the benthic foraminiferal communities
2. The influence of different sedimentation regimes on abundances

Regarding the first point, a recent study by Caridi et al. (2026, in press; preprint at http://dx.doi.org/10.2139/ssrn.5624076) showed different CTD profiles, indicating that the presence of HSSW is confined to the outer part of the bay, while in the inner part a slightly warmer bottom water is present (a modified version of mCDW). Reviewer #2 proposes a compelling explanation for the agglutinated versus calcareous pattern, namely the presence of brine-enriched bottom water. However, the oceanographic data presented in Caridi et al. (2026, in press) show no evidence of such a process influencing community structures, at least at the time when the CTDs were deployed. Furthermore, the Eh values shown in Figure 2 highlight the presence of dissolution conditions regardless of the presence of HSSW. In addition, tidal forcing appears to be an important contributing factor in controlling the hydrographic regimes in this area. Furthermore, to provide a broader context for the modern environment, other cores retrieved in the area show an order-of-magnitude drop in sedimentation rates around 700 yrs BP (Galli et al., 2023; Tesi et al., 2020), with values similar to those reported in Table 1. This implies a more localized and less regionally controlled environment respect to the Late Holocene.

Hence, while different water masses offer a compelling explanation for the modern environmental and ecological settings, we believe that a more local and synergistic effect of organic matter, hydrodynamic regime, oxygen availability, and grain size has produced the community patterns shown in the manuscript. However, we agree with both reviewers that there is a lack of oceanographic context in the manuscript that could help elucidate these questions and aid the reader. We will therefore add information consistent with what is described above in Section 1.1 (Line 100), where we will briefly explain the results from Battaglia et al. (2024) and Caridi et al. (2026, in press).

The second main point of discussion concerns the presence of different sediment accumulation rates from the inner part of the fjord to the outer areas and their contribution to structuring the dead assemblage.

Reviewer #1 suggests that high sedimentation rates in the inner part of the bay could lead to dilution of the concentration of tests per gram of dry sediment, while in the outer bay the presence of strong hydrodynamics could result in sediment winnowing, thus concentrating the number of tests. Especially in the outer bay, a high bottom-current regime could reduce the fine sediment fraction, producing the observed discrepancy (as shown in Figure 5). We thank Reviewer #1 for this observation and agree that this process could represent a taphonomic factor enhancing the discrepancy between the inner and outer parts of the fjord. We will add this process as a possible contributing factor in Section 4.2.

Furthermore, Reviewer #2 suggests that planktonic foraminifera abundance could be biased by the same type of effect proposed by Reviewer #1. However, as reported in the raw counts presented in the supplementary material, outer-bay sediment cores show no planktic foraminifera except in the 0–1 cm interval, whereas the inner bay contains planktic foraminifera throughout the upper 5 cm (as also shown in Figure 2). While absolute values may be misleading, the relative disproportion between the inner and outer parts of the bay with respect to planktic foraminifera suggests the presence of different primary productivity regimes, rather than a bias arising solely from differences in sedimentation regime.

Another important concern raised by Reviewer #2 relates to the reliability of the organic carbon data. The samples were retrieved in March 2024, transported under controlled thermal conditions, and analyzed the following year (March 2025). Our organic carbon analysis focused on total organic carbon (TOC) rather than on the specific nature of the organic matter (fresh vs. labile). Therefore, since we adopted standard procedures to analyze the total organic carbon content (as explicitly described in Section 2.2), and since the target of our analysis was not bioavailable carbon, we believe that the time elapsed between collection and analysis did not have a substantial effect on the measurements.

We hope to have been exhaustive on this first concerns.

On behalf of all co-authors,

Giacomo Galli

First, we would like to thank both reviewers for acknowledging the novelty of our study, for showing interest and enthusiasm in our work, and for raising important questions and comments about our findings.

While we reserve the opportunity to correct additional grammatical errors and to respond more specifically to the questions highlighted by the reviewers in a subsequent interaction, we would like to address the most important concerns raised in their reports:

1. The influence of water masses (mCDW, HSSW, and/or brine production) on the benthic foraminiferal communities
2. The influence of different sedimentation regimes on abundances

Regarding the first point, a recent study by Caridi et al. (2026, in press; preprint at http://dx.doi.org/10.2139/ssrn.5624076) showed different CTD profiles, indicating that the presence of HSSW is confined to the outer part of the bay, while in the inner part a slightly warmer bottom water is present (a modified version of mCDW). Reviewer #2 proposes a compelling explanation for the agglutinated versus calcareous pattern, namely the presence of brine-enriched bottom water. However, the oceanographic data presented in Caridi et al. (2026, in press) show no evidence of such a process influencing community structures, at least at the time when the CTDs were deployed. Furthermore, the Eh values shown in Figure 2 highlight the presence of dissolution conditions regardless of the presence of HSSW. In addition, tidal forcing appears to be an important contributing factor in controlling the hydrographic regimes in this area. Furthermore, to provide a broader context for the modern environment, other cores retrieved in the area show an order-of-magnitude drop in sedimentation rates around 700 yrs BP (Galli et al., 2023; Tesi et al., 2020), with values similar to those reported in Table 1. This implies a more localized and less regionally controlled environment respect to the Late Holocene.

Hence, while different water masses offer a compelling explanation for the modern environmental and ecological settings, we believe that a more local and synergistic effect of organic matter, hydrodynamic regime, oxygen availability, and grain size has produced the community patterns shown in the manuscript. However, we agree with both reviewers that there is a lack of oceanographic context in the manuscript that could help elucidate these questions and aid the reader. We will therefore add information consistent with what is described above in Section 1.1 (Line 100), where we will briefly explain the results from Battaglia et al. (2024) and Caridi et al. (2026, in press).

The second main point of discussion concerns the presence of different sediment accumulation rates from the inner part of the fjord to the outer areas and their contribution to structuring the dead assemblage.

Reviewer #1 suggests that high sedimentation rates in the inner part of the bay could lead to dilution of the concentration of tests per gram of dry sediment, while in the outer bay the presence of strong hydrodynamics could result in sediment winnowing, thus concentrating the number of tests. Especially in the outer bay, a high bottom-current regime could reduce the fine sediment fraction, producing the observed discrepancy (as shown in Figure 5). We thank Reviewer #1 for this observation and agree that this process could represent a taphonomic factor enhancing the discrepancy between the inner and outer parts of the fjord. We will add this process as a possible contributing factor in Section 4.2.

Furthermore, Reviewer #2 suggests that planktonic foraminifera abundance could be biased by the same type of effect proposed by Reviewer #1. However, as reported in the raw counts presented in the supplementary material, outer-bay sediment cores show no planktic foraminifera except in the 0–1 cm interval, whereas the inner bay contains planktic foraminifera throughout the upper 5 cm (as also shown in Figure 2). While absolute values may be misleading, the relative disproportion between the inner and outer parts of the bay with respect to planktic foraminifera suggests the presence of different primary productivity regimes, rather than a bias arising solely from differences in sedimentation regime.

Another important concern raised by Reviewer #2 relates to the reliability of the organic carbon data. The samples were retrieved in March 2024, transported under controlled thermal conditions, and analyzed the following year (March 2025). Our organic carbon analysis focused on total organic carbon (TOC) rather than on the specific nature of the organic matter (fresh vs. labile). Therefore, since we adopted standard procedures to analyze the total organic carbon content (as explicitly described in Section 2.2), and since the target of our analysis was not bioavailable carbon, we believe that the time elapsed between collection and analysis did not have a substantial effect on the measurements.

We hope to have been exhaustive on this first concerns.

On behalf of all co-authors,

Giacomo Galli

First, we would like to thank both reviewers for acknowledging the novelty of our study, for showing interest and enthusiasm in our work, and for raising important questions and comments about our findings.

While we reserve the opportunity to correct additional grammatical errors and to respond more specifically to the questions highlighted by the reviewers in a subsequent interaction, we would like to address the most important concerns raised in their reports:

1. The influence of water masses (mCDW, HSSW, and/or brine production) on the benthic foraminiferal communities
2. The influence of different sedimentation regimes on abundances

Regarding the first point, a recent study by Caridi et al. (2026, in press; preprint at http://dx.doi.org/10.2139/ssrn.5624076) showed different CTD profiles, indicating that the presence of HSSW is confined to the outer part of the bay, while in the inner part a slightly warmer bottom water is present (a modified version of mCDW). Reviewer #2 proposes a compelling explanation for the agglutinated versus calcareous pattern, namely the presence of brine-enriched bottom water. However, the oceanographic data presented in Caridi et al. (2026, in press) show no evidence of such a process influencing community structures, at least at the time when the CTDs were deployed. Furthermore, the Eh values shown in Figure 2 highlight the presence of dissolution conditions regardless of the presence of HSSW. In addition, tidal forcing appears to be an important contributing factor in controlling the hydrographic regimes in this area. Furthermore, to provide a broader context for the modern environment, other cores retrieved in the area show an order-of-magnitude drop in sedimentation rates around 700 yrs BP (Galli et al., 2023; Tesi et al., 2020), with values similar to those reported in Table 1. This implies a more localized and less regionally controlled environment respect to the Late Holocene.

Hence, while different water masses offer a compelling explanation for the modern environmental and ecological settings, we believe that a more local and synergistic effect of organic matter, hydrodynamic regime, oxygen availability, and grain size has produced the community patterns shown in the manuscript. However, we agree with both reviewers that there is a lack of oceanographic context in the manuscript that could help elucidate these questions and aid the reader. We will therefore add information consistent with what is described above in Section 1.1 (Line 100), where we will briefly explain the results from Battaglia et al. (2024) and Caridi et al. (2026, in press).

The second main point of discussion concerns the presence of different sediment accumulation rates from the inner part of the fjord to the outer areas and their contribution to structuring the dead assemblage.

Reviewer #1 suggests that high sedimentation rates in the inner part of the bay could lead to dilution of the concentration of tests per gram of dry sediment, while in the outer bay the presence of strong hydrodynamics could result in sediment winnowing, thus concentrating the number of tests. Especially in the outer bay, a high bottom-current regime could reduce the fine sediment fraction, producing the observed discrepancy (as shown in Figure 5). We thank Reviewer #1 for this observation and agree that this process could represent a taphonomic factor enhancing the discrepancy between the inner and outer parts of the fjord. We will add this process as a possible contributing factor in Section 4.2.

Furthermore, Reviewer #2 suggests that planktonic foraminifera abundance could be biased by the same type of effect proposed by Reviewer #1. However, as reported in the raw counts presented in the supplementary material, outer-bay sediment cores show no planktic foraminifera except in the 0–1 cm interval, whereas the inner bay contains planktic foraminifera throughout the upper 5 cm (as also shown in Figure 2). While absolute values may be misleading, the relative disproportion between the inner and outer parts of the bay with respect to planktic foraminifera suggests the presence of different primary productivity regimes, rather than a bias arising solely from differences in sedimentation regime.

Another important concern raised by Reviewer #2 relates to the reliability of the organic carbon data. The samples were retrieved in March 2024, transported under controlled thermal conditions, and analyzed the following year (March 2025). Our organic carbon analysis focused on total organic carbon (TOC) rather than on the specific nature of the organic matter (fresh vs. labile). Therefore, since we adopted standard procedures to analyze the total organic carbon content (as explicitly described in Section 2.2), and since the target of our analysis was not bioavailable carbon, we believe that the time elapsed between collection and analysis did not have a substantial effect on the measurements.

We hope to have been exhaustive on this first concerns.

On behalf of all co-authors,

Giacomo Galli