Report No.	D005
Monitoring Period	March - May 2014

Investigation Report Attachment

1. Review all available and relevant data (construction activities), including raw data and analyses of other parameters (air, noise, water and underwater acoustic) covered in the EM&A, to ascertain if differences are a result of natural variation or previously observed seasonal differences.

The data from water quality from the reporting quarter were reviewed no project related water quality exceedence for HKBCF was recorded during March – May 2014. In addition, on review of recent AFCD annual monitoring reports (AFCD 2014; 2013; 2012; 2011), it is stated that a decline in dolphin density and abundance has been apparent in all areas of Hong Kong for some time. Further a summary of a regression analyses presented in last year’s report (AFCD 2013) shows that there has been a significant decrease in dolphin abundance since the early 2000’s, more than a decade prior to Project commencement. A paper published which incorporates data from throughout the populations known extent, confirms the ongoing and severe decline of the dolphin population and estimates that 74.27% of the population will be lost within the next three generations (Huang et al 2012). Moreover, it is predicted that the current calculated rate is likely to accelerate given what is understood from other cetacean population collapses in the South China Sea region. There was no similar population modeling conducted as part of the EIA for this Project, however, the EIA reports this decline and from information therein and the data currently available from elsewhere, there is a well-documented and substantial population decline. Given that the population has been in significant decline since prior to Project onset and as there has been no recorded exceedences of this Projects water quality plus all dolphin monitoring has been conducted as per EM&A Manual, there is no evidence to indicate a direct link between this Project and the encounter rates throughout the NWL and NEL area for March – May 2014.

2. Identify source(s) of impacts.

There is a documented significant population decline of the Hong Kong dolphin and, as yet, no detailed assessment of causal factors is available. Recent population modelling studies do show a significant and, possibly, accelerating population decline since 2000 (see 1) and, prior to 2008, an expert panel concluded that the anthropogenic activities which occur in the Hong Kong and adjacent habitat which have considerable potential to affect the PRE dolphin population through pollution, infection, lowered prey availability, intense and low noise levels, collisions, behavioural changes, disturbance, entanglement in fishing gear and habitat modification are; construction, dredging, sewage disposal, industrial effluent discharge, shipping, reclamation, fishing. Since this review, pro-active management by AFCD has resulted in a reduction of the negative impacts caused by non-sustainable fishing (as the trawling ban progresses “lowered prey availability” should alter) and a general reduction in fishing activities will reduce the potential for entanglement in fishing gear. Other identified impacts, however, are ongoing and it is noted that construction activities and the high speed ferry traffic in NEL and NWL have both increased since 2008 (AFCD Annual Monitoring Reports 2009;2010;2011;2012;2013;2014). It is known from studies elsewhere that dredging and all piling activities cause significant disturbance to marine mammals (David 2006; Jefferson et al. 2009; Bailey et al 2010). These activities do not occur as part of this Project but may do elsewhere in the NEL and NWL areas as well as in Hong Kong and adjacent habitat. Activities which are stressful to dolphins are usually associated with increased underwater noise levels. Sources of increased underwater noise levels in NEL and NWL include, but may not be limited to;

- HZMB Project marine construction work (all areas, some areas involve piling)

- Other marine works in Hong Kong waters (extensive dredging was reported in NWL as part of shipping lane maintenance)

- Vessel traffic (this Project, HZMB projects, other infrastructure projects and, of course, Hong Kong and adjacent waters are the world’s busiest port facility with heavy shipping traffic)

- Other activities that may catalyse a shift in habitat use that is not noise related is an alteration in prey resources. And further, an analysis of the cumulative impact of all of these anthropogenic impacts has yet to be conducted.

Further, a recent publication (Gui et al 2014) indicated that the dolphins which live in the Pearl River Estuary are subject to high levels of pollution and analyses tissue samples show both bioaccumulation and biomagnification of heavy metals and persistent organic pollutants (POPs). This indicates the health status of the dolphin population is poor and may have been be impacting population reproductive success and mortality rates for decades.

3. Repeat review to ensure all the dolphin protective measures are fully and properly implemented and advise if additional measures are necessary.

Site inspection of the implementation of vessel speed limit, acoustic decoupling measures, spillage and runoff prevention measures on barges, training records related to regular marine travel routes for Contract’s vessels, record of implementation of dolphin watching plan and silt curtain integrity checking record were conducted during weekly site inspection. The appropriate mitigation was in place depending on site activities, i.e., Dolphin Exclusive Zone for silt curtain laying (if any) and Dolphin Watching Plan for all other Project activities.

4. Investigate whether the exceedance was caused by any of the construction activity associated with the works contract.

No construction works associated with the Project can be found to coincide with the observed dolphin encounter rates.

In summary, no causal relationship with any one construction activity at the Project site can be found to link directly with the reduced habitat use of NEL and NWL during March – May 2014. NWL has seen increasing work activities not as part of this project works. In addition, It was observed that both NEL and NWL areas have been affected by construction and transport activities which are not related to this Contract. These activities may cause impact to marine mammals, usually manifested as a shift in distribution although we do not yet know the long term effect of these activities which are not part of this Contract.

Although no unacceptable changes in environmental parameters of this project have been measured, at this time it is not possible to make a conclusive assessment of this Project’s specific impact on dolphins.

References

AFCD Monitoring Report. From: http://www.afcd.gov.hk/english/conservation/con_mar/con_mar_chi/con_mar_chi_chi/con_mar_chi_chi.html

Bailey, H., Senior, B., Simmons, D., Rusin, J., Picken, G., & Thompson, P. M. (2010). Assessing underwater noise levels during pile-driving at an offshore windfarm and its potential effects on marine mammals. Marine Pollution Bulletin,60 (6), 888-897.

David, J.A. (2006). Likely sensitivity of bottlenose dolphins to pile-driving noise. Water and Environment Journal 20:48–54

Jefferson, T. A., Hung, S. K., & Würsig, B. (2009). Protecting small cetaceans from coastal development: Impact assessment and mitigation experience in Hong Kong. Marine Policy, 33(2), 305-311.

Huang , S.L., Karczmarski, L., Chen, J, Zhou, R., Lin, W., Zhang, H., Li, H. and Wu, Y.P. (2012). Demography and population trends of the largest population of Indo-Pacific humpback dolphins. Conservation Biology 147(1):234-42

Gui, D., Yu, R., He, X., Tu, Q., Chen, L., and Wu, Y. (2014) Bioaccumulation and biomagnification of persistent organic pollutants in Indo-Pacific humpback dolphins (Sousa chinensis) from the Pearl River Estuary, China. Chemosphere Volume 114, November 2014, Pages 106–113