The Effects of Live Feeding on Swimming Activity and Exhibit Use in Zoo Humboldt Penguins (Spheniscus humboldti)
Round 1
Reviewer 1 Report
The paper describes live feeding as a tool for improving animal welfare by increasing animal activity. The paper is well written and provides important data for this species. If I were to do this project at my institution I would require animal ethics because fish are vertebrates, and we are not allowed to feed live vertebrates to other animals under law. I assume this is not that case in America as there was no mention of animal ethics approvals in the paper or acknowledgements. If approvals were obtained approval numbers should be included in the manuscript. If this is irrelevant please ignore. There are some minor details about how penguins were fed on ‘other’ days that I think should be included as those days make up the majority of data so it is important to know what was happening on those days as well.
Minor comments:
L131-141 - You could include some information here on what and how penguins were fed on non-live feeding days, are they fed on land on the non-live feeding days? If they are being hand fed by a keeper on those days, there would be a portion of time they would be on land just so they can eat - this may be a point that need further discussion in the Discussion section. Are they fed at the same time (11am) on non-live feed days?
L225-235 - Is it possible that factors other than visitors are affecting their behaviour? For example, are there any changes to husbandry procedures on weekends? Do they get fed at the same times, same quantities and food types?
L253 predating – the dictionary definition of this word is “exist or occur at a date earlier than (something)” I would suggest changing this word to hunting
Author Response
Please see attached revision notes.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
- Detailed describtion of investigated animals is needed (e.g. age, sex, families, fitness etc.).
- The outdoor exhibit is newly developed. Were the animals moved to the exhibit just before the investigation, or did they have time to adapt to the new environment?
- Description of behaviors is needed (Swimming, Grooming, Land Activity).
- What was the regular (non-live) feed for the animals? Was it also fed at the same time every day (11 a.m.)?
- How many times have the penguins been fed and at what time?
- Figure 5, 6 and 7: "Non-Feed" explanation should be changed to "Non-Live" or "Non-Live Feed".
- What do you think about the impact of live feed on the competition of the penguins? Did all tested animals have acces to enough feed, or were some of them "bad" predators and lost in competitions?
- The presented research is more than 10-year-old. What new investigations have been performed since that time?
- What are the practical benefits of the study? Have the "Live Feeding" procedure been introduced in the zoo?
Author Response
Please see attached revision notes.
Author Response File: Author Response.pdf
