# PS5 - EEP101/ECON125 Spring 99 Prof D Zilberman TAs...

This preview shows pages 1–2. Sign up to view the full content.

EEP101/ECON125 Spring 99 Prof. D. Zilberman TA’s: Malick/Marceau PROBLEM SET 5 Due Monday May 10, in your TA’s mailbox 1. Controlled dehorning of rhinos has been proposed as a way of reducing poaching and raising income for wildlife management programs in Africa. Milner-Gulland et al. (1992) 1 calculated the optimal frequency at which to crop African rhinos. This exercise is a simplified version of their model. They found that the growth of a rhinos horn obeys the equation 3 87 . 0 ) 8 . 0 1 ( 3 ) ( t e t Q - - = where Q(t) is the mass in kg after t years. It costs \$960 to remove a 3 kg horn and the price is \$750 per kg. Interest rates in African countries tend to be quite high, around 10% - 30%. (a) Using the single rotation forestry model (no replanting) and an interest rate of 10%, determine how long a rhino horn should be allowed to grow before removing it. (b) The authors actually argue that “the optimum rotation period will not usually exceed 3 years”. (i) What factor(s) would shorten the optimal rotation time to something less than what you calculated in part (a)? (Hint: Rhino horn will regrow rather quickly once it is cut.) (ii) What factor(s) might explain more frequent dehorning in reality?

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern