Nino

Take your time, settle down, if you want you can…return

Well, sometimes it is about fathers and sons, but sometimes it is also about sisters and unrelated males to find each other and settle down…

Three months after the beginning of our fieldwork we finally recorded our first long-range dispersal event. Following aggressive eviction from the natal group, a dispersing coalition of five subordinate females joined a group of unrelated roving males and left the core study area. The newly- formed group went undetected for several weeks until Nino found one of the coalition members (VLF152) …back on the reserve where she was captured and collared 5 weeks before. Interestingly enough she wasn’t with any of her original coalition partners and instead paired up with two newly evicted sisters.

Dispersal event of one female (VLF152) from the five-members dispersing coalition showing a typical migration pattern (see Bunnefeld et al. 2011, Börger and Fryxel 2012) as represented by the increasing and subsequent decreasing distance from the site of capture (origin). VLF152 returned home after a 25 km round trip lasting 31 days. The other four coalition members have not returned and possibly established a new territory (red circle), following a typical dispersal pattern (left side of the blue dotted line) characterized by departure (1) roaming (2) and settlement (3).
Dispersal event of one female (VLF152) from the five-members dispersing coalition showing a typical migration pattern (see Bunnefeld et al. 2011, Börger and Fryxel 2012) as represented by the increasing and subsequent decreasing distance from the site of capture (origin). VLF152 returned home after a 25 km round trip lasting 31 days. The other four coalition members have not returned and possibly established a new territory (red circle), following a typical dispersal pattern (left side of the blue dotted line) characterized by departure (1) roaming (2) and settlement (3).

But where were the other four sisters? Did the coalition simply split or did the other die? Or did they settled down somewhere with the males? But if so, why did VLF152 “return home” instead or remaining within them? Is this because, even within the new group, she was occupying a low rank and had therefore no chance of reproducing (for only one female, the dominant female, reproduces within a group)? We are currently trying to find the other four females to answer some of our questions. Knowing the where about of VLF152 – information that we can remotely download from her GPS collar – should help in this task since we can restrict our search radius.

This dispersal event adds to the previously collared individuals. At present, three dispersal coalitions returned to the natal group, one female returned to the natal group after her coalition partner got hit by a car but got evicted again, three coalitions are still dispersing and one single disperser got predated by a raptor. We thus recorded two cases of dispersal-related mortality. These movement data will allow us to investigate the influence that individual traits (e.g. age, size) but also the environment and the social spatial context (i.e. the distribution of territorial groups) have on dispersal patterns and dispersal success (survival rate and settlement likelihood).

Preliminary movement data from eight dispersing coalitions fitted with GPS radio collars. Each color represents the trajectory of a different dispersing unit in (A) the environmental landscape and (B) the social context. Note the long-range dispersal event southwest of VLF152 (violet/pink)! In (B) a utilization distribution map for the main study area is created based on the location of territorial groups (warm color= high encounter likelihood, cold colors= low encounter likelihood); long range dispersal event may end in areas where the social context is unknown (white)
Preliminary movement data from eight dispersing coalitions fitted with GPS radio collars. Each color represents the trajectory of a different dispersing unit in (A) the environmental landscape and (B) the social context. Note the long-range dispersal event southwest of VLF152 (violet/pink)! In (B) a utilization distribution map for the main study area is created based on the location of territorial groups (warm color= high encounter likelihood, cold colors= low encounter likelihood); long range dispersal event may end in areas where the social context is unknown (white)

!!!   Merry Christmas from us all and a successful 2014   !!!

Well begun is half done

After 5 weeks spent in South Africa it is time to draw the first conclusions regarding our new-born project on dispersal in meerkats. I do not want to sound presumptuous but I feel confident saying that this trip has been a great success. And as you know…well begun is half done. But let’s start with some facts from the field.

After few days spent testing the new collars and equipment, getting familiar with the terrain and the road system on the reserve, and getting to know all researchers and volunteers working at the Kalahari Meerkat Project, things got suddenly hectic when one morning we received a radio call from Teja (one of the volunteers) saying that she sighted a female evicted by her natal group a few weeks before being chased by some members of the neighboring group. We could not miss that chance, our first evicted female!

A breathing mask is applied over the head of the meerkat while it is still in the pillow case
A breathing mask is applied over the head of the meerkat while it is still in the pillow case

In few minutes and with the much-appreciated help of Lewis and Sky (the project field managers) we prepared the equipment to capture and anesthetize what turned out to be VLF143 (or spelled out: Female 143 of the Lazuli group). It took only a split second for Sky to close his fingers around the base of the tail of VLF143 that, without even noticing, found herself rowing with the four legs in the air before being gently put in a pillow case to be immobilized. Sky and Lewis applied a breathing mask with a mixture of Isoflurane and Oxygen over her head and in few seconds VLF143 was fast asleep. Few minutes later she was up and running again and, as if nothing happened, she resumed her activities. But this time with a collar around her neck.  In the following 13 days, thanks to the precious calls of the volunteers – our eyes on the reserve – we successfully collared additional 3 females (VEKF010, VJXF035 and VAZF027) from 3 different groups. Hopefully, by the end of this first field season, we will have collared a total of 10 females.

We are closely monitoring each collared individual to make sure that the collars do not negatively influence the animals and to collect important behavioral and ecological data. Daily observations already allowed collecting important information that will allow fine-tuning our research questions. GPS movement data automatically recorded by the collars at one-hour interval during daytime will be analyzed as a function of environmental factors (e.g. rainfall, temperature), social circumstances (e.g. number of individuals in the dispersing coalition but also their location in relation to unrelated territorial groups) and the animal’s individual state (e.g. body condition, stress level). In the long run, we aim to use information on dispersing individuals such as survival rate and reproductive success to improve already existing population dynamic models.

Close follows up are essential to record important behavioural and ecological information and to keep the animals habituated to researchers
Close follows up are essential to record important behavioural and ecological information and to keep the animals habituated to researchers

The first days of our monitoring already provided us with some very useful information. Female VJXF035 lost her sister (VJXF039) with whom she was travelling with after a car run her over. VJXF035 is now back with her group after the dominant female allowed her to rejoin. The collar that we fitted on female VAZF027 (who was dispersing alone) got found lying on the ground…without VAZF027. The collar was covered in blood and fur indicating that VAZF027 got predated, most likely by a raptor. Female VLF143 seems to have found a clever strategy to avoid spending too much time alone (the more eyes scanning around the lower the chance to be taken by a raptor of course); she has already associated, and mated, with 8 different males… I spare you the details. We hope that sooner or later she will build a somehow more stable bond with one or more males and that they will soon set off to find their own territory. Female VEKF010 seems to be the more enterprising and has already crossed the territory of two foreign groups. She has occasionally associated with a couple of males but she seems to be prioritizing a disperser’s business (the actually dispersing) to  a disperser’s pleasure (I believe it is clear what I am referring to…).

Movements of four collared females in and around Kuruman River Reserve, home to the Kalahari Meerkat Project
Movements of four collared females in and around Kuruman River Reserve, home to the Kalahari Meerkat Project

While I had to return to the foggy and miserable Zurich weather, Nino will remain in the sunny Kalahari until the end of March and will continue monitoring dispersing individuals. More info will follow soon.

Necklaces for the girls, cars for the boys – Preparations for the first meerkat field season

Cable tie and epoxy instead of diamonds

My name is MaagNino Maag, and I am about to start my PhD in the Population Ecology lab. During my study, I will investigate dispersal strategies in a wild population of the Kalahari meerkat (Suricata suricatta) in South Africa. I will use high-resolution GPS telemetry data collected from GPS radio collared dispersing female subordinates to investigate the influence of individual traits, environmental factors and social context on transition and settlement strategies. Furthermore, I will assess the survival rates of dispersing females during the stages of transition and settlement. The results of my study shall provide the complementary information on dispersal for more comprehensive spatially explicit population dynamics models and the investigation of alternative life history strategies.

Alex is applying the epoxy.
Alex is applying the epoxy.

In order to acquire movement data of the dispersing individuals, we had to prepare GPS collars. However, two days before leaving for South Africa, the GPS collars yet had to be built. For this reason we set up a workshop in our office in Zurich. On Monday afternoon, 23 September, Gabriele and I were supposed to take a plane to Johannesburg and on Saturday morning we started the workshop. Alex, engineer at CDD Ltd in Athens, followed in for the weekend to build the collars with us.

GPS collar.
GPS collar.

Since meerkats are small animals and we plan to collect detailed dispersal data in an extended area over a time period of six months, GPS collars have to meet a set of specific requirements: The weight has to be below 25 grams, the coating must be robust but should not interfere with the GPS signal, the belting can not be too edgy, and both the GPS data collection schedule and the bidirectional remote communication regime (ZigBee) should be as frequent but in the same time as economic as possible. The GPS device, VHF sender, ZigBee component, and battery were coated with epoxy. We applied cable tie as belting, which will later get covered with heat shrink to make the edges smooth. The epoxy may not be as shiny as diamonds, but the girls will still be fitted with decent solid necklaces.

After a hard weekend’s work, which lasted until Monday noon, Gabriele and I just managed to catch the plane in the afternoon.

Big cars for big boys

In the early Tuesday morning, Gabriele and I arrived in Johannesburg. I bought some airtime and data for my iPhone, Gabriele a new cell phone. After that we picked up the rental car and headed out to buy a field vehicle. Equipped with a Kia picanto and a Tomtom, everything was prepared for the day becoming a successful journey. I have to tell you though, Johannesburg is quite a big city and it took time to visit the different car dealers in the different neighborhoods, especially without a street map. Fortunately, our hosts Nancy and Greg at the Strathavon bed and breakfast were very nice and, besides offering an extra bedroom for free, provided us with a street map, which enabled us to plan next day’s car search a lot more efficient.

Two experts do the technical examination of our Toyota Hilux.
Two experts do the technical examination of our Toyota Hilux.

On Wednesday afternoon we tried our luck in Pretoria. That was a smart move as we found two nice vehicles on that day. Two good-looking Toyota Hilux 3.0 4×4, both were diesel and in good condition. Just the type of car we need! On Thursday we even found a third one. All three dealers agreed to bring their vehicle to a mechanic for full mechanical examination. Well, I had to learn that you should not trust these people too much. One changed his mind and did not bring the car at all, and the second one sold the car to someone else while we were making the technical examination. First comes, first serves! That left us with only one car, a Toyota Hilux 3.0 Diesel 4×4 KZ-TE 2004. To be honest, that was the best one anyway. What a nice car!

Our new hosts Jenny and Pat, the owners of the Sengwe Place bed and breakfast, provided us with an entire apartment. They are such friendly and welcoming people, and, besides a lot of other things, they helped us to buy insurance for the car. On Friday we will hit the road and eventually drive to the field site near Van Zylsrus, Northern Cape. Lets chase some meerkats.

Nino Maag | PhD Student

I am an ecologist and I want to know how animals move through space and time, how they perform in changing environments, and how these factors affect their life histories. My research interests are population ecology, dispersal ecology and evolution, life-history theory, movement ecology, population demography, landscape genetics, and conservation biology. During my MSc, I investigated the influence of a dynamic water regime on gene flow between local populations of a riparian grasshopper species. After my MSc, I worked as a research assistant on the effects of climate change on Alpine bird species that are indicative for structural diversity in mountain forests.

In 2014, I started my PhD thesis at the Population Ecology Research Group in Zurich. By fitting light-weight GPS collars on dispersing female meerkats, I investigate the influence of social and environmental factors on different dispersal strategies. Assessment of how these factors affect individual state variables during dispersal, and how those variables affect survival and reproduction, will improve our understanding of alternative life-history strategies and their consequences for population dynamics.

Beyond research, I love nature and doing outdoor sports such as hiking, climbing, ski touring, cycling, swimming and diving.

 

 

CV

  • 2014-present, PhD student, Population Ecology Research Group, University of Zurich, Switzerland
  • 2013-2014, Field manager, Meerkat Dispersal Project, Kalahari Research Station, South Africa
  • 2011-2012, Research Assistant, Swiss Federal Research Institute, WSL, Switzerland
  • 2010-2011, MSc in Ecology, University of Zurich, Switzerland
  • 2006-2009, BSc in Biology, University of Zurich, Switzerland

 

Publications

  • Maag N, Cozzi G, Clutton-Brock T, Ozgul A (submitted) Density-dependent dispersal strategies in a cooperative breeder. PNAS
  • Cozzi G, Maag N, Börger L, Clutton-Brock T, Ozgul A (In review) Socially informed dispersal in a territorial cooperative breeder. Journal of Animal Ecology
  • Maag N, Karpati T, Bollmann K (2013) Semi-natural river system maintains functional connectivity and gene flow of the critically endangered gravel grasshopper (Chorthippus pullus). Biological Conservation 158:88–97
  • Maag N, Gehrer L, Woodhams DC (2012) Sink or swim: a test of tadpole behavioral response to predator cues and potential alarm pheromones from skin secretions. Journal of Comparative Physiology – A 198:841–846

Individual strategies, group dynamics and population regulation in cooperative breeders

meerkatsMany species live in socially and spatially structured populations, and the behavioural, evolutionary, and demographic aspects of sociality have been the focus of much theoretical and empirical research. One major shortcoming of the empirical work, due mainly to practical considerations, has been its focus on already-established social groups (either in captivity or in the wild) and its omission of complexity in between-group processes, such as dispersal and new group formation. Natal dispersal of individuals, immigration into existing groups, and new group formation are latent but crucial aspects of dynamics in socially and spatially-structured populations.  The high fitness costs associated with each stage of dispersal (emigration, transience, and settlement) are likely to induce strong selective pressures on within-group social strategies that directly or indirectly relate to dispersal: e.g., inbreeding avoidance, reproductive suppression, mate finding strategies, helping behaviours, etc. The fitness consequence of these social strategies cannot be accurately assessed, and investigations of behavioural, evolutionary, and demographic processes are therefore incomplete, without a socially and spatially explicit approach that accounts for between-group processes.

In this research, we bring together theoretical models, novel telemetry data on dispersal, and long-term individual-based data on within-group processes to provide a spatially explicit investigation of the life history strategies in a cooperatively breeding mongoose, the Kalahari meerkat. Using this new perspective, we will be able to re-evaluate the fitness consequences of alternative social and behavioural strategies while accounting for dispersal in particular and between-group processes in general at an unprecedented detail level.

 

In collaboration with: