Early detection and recovery of river herring spawning habitat use in response to a mainstem dam removal.

Historical loss of river and stream habitats due to impassable dams has contributed to the severe decline of many fish species. Anadromous fishes that migrate from the sea to freshwater streams to spawn have been especially impacted as dams restrict these fish from accessing ancestral spawning grounds. In 2018, Bloede Dam was removed from the Patapsco River near Baltimore, Maryland, restoring approximately 100 km of potential habitat for migratory fish. We assessed the response of anadromous river herring, alewife (Alosa pseudoharengus) and blueback herring (Alosa aestivalis), to this dam removal by monitoring environmental DNA (eDNA) and eggs from 2015 to 2021 at locations upstream and downstream of the dam site during their spawning migrations. We additionally assessed the presence of fish by collecting electrofishing samples and tracked the movements of individual adult fish within the river using passive integrated transponder (PIT) tags. No adult river herring, eDNA, or eggs were detected upstream of Bloede Dam in the four years prior to its removal despite the presence of a fish ladder. Our results suggest initial habitat use recovery by spawning river herring in the first year post-removal, although a relatively small proportion of the population in the river used the newly accessible habitat. In the three years post-removal, the likelihood of detecting river herring eDNA upstream of the former dam site increased to 5% for alewife and 13% for blueback herring. Two adult fish were also collected in electrofishing samples upstream of the dam site in 2021. We found no evidence of changes in egg abundance and no tagged fish were detected upstream of the dam site post-removal. While long term monitoring is needed to assess population changes, this study highlights the value of integrating methods for comprehensive understanding of habitat use following dam removal.

What is the quality of smoking cessation advice in guidelines of tobacco-related diseases?

Smoking is a major risk factor for a range of diseases, and quitting smoking provides considerable benefits to health. It therefore follows that clinical guidelines on disease management, particularly for diseases caused by smoking, should include smoking cessation. The aim of this study was to determine the extent to which this is the case. We conducted a systematic review investigating clinical guidelines and recommendations issued by UK national or European transnational medical speciality associations and societies issued between 2000 and 2012 on a range of diseases caused by smoking. We then investigated whether selected guidelines contained reference to smoking cessation and smoking cessation advice. Although the extent to which smoking and smoking cessation was mentioned in the guidelines varied between diseases, only 60% of guidelines identified recognised that smoking is a risk factor for the development of the disease and 40% recommended smoking cessation. Only 19% of guidelines provided detailed information on how to deliver smoking cessation support. Smoking cessation is not comprehensively addressed in current UK and transnational European clinical practice guidelines and recommendations.